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Note: This page contains sample records for the topic "thermal depletion model" from the National Library of EnergyBeta (NLEBeta).
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they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
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1

Application of thermal depletion model to geothermal reservoirs...  

Open Energy Info (EERE)

of thermal depletion model to geothermal reservoirs with fracture and pore permeability Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Conference Proceedings:...

2

Application of thermal depletion model to geothermal reservoirs with  

Open Energy Info (EERE)

thermal depletion model to geothermal reservoirs with thermal depletion model to geothermal reservoirs with fracture and pore permeability Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Conference Proceedings: Application of thermal depletion model to geothermal reservoirs with fracture and pore permeability Details Activities (2) Areas (2) Regions (0) Abstract: If reinjection and production wells intersect connected fractures, it is expected that reinjected fluid would cool the production well much sooner than would be predicted from calculations of flow in a porous medium. A method for calculating how much sooner that cooling will occur was developed. Basic assumptions of the method are presented, and possible application to the Salton Sea Geothermal Field, the Raft River System, and to reinjection of supersaturated fluids is discussed.

3

Depletion modeling of liquid dominated geothermal reservoirs  

DOE Green Energy (OSTI)

Depletion models for liquid-dominated geothermal reservoirs are derived and presented. The depletion models are divided into two categories: confined and unconfined. For both cases depletion models with no recharge (or influx), and depletion models including recharge, are used to match field data from the Svartsengi high temperature geothermal field in Iceland. The influx models included with the mass and energy balances are adopted from the petroleum engineering literature. The match to production data from Svartsengi is improved when influx was included. The Schilthuis steady-state influx gives a satisfactory match. The finite aquifer method of Fetkovitch, and the unsteady state method of Hurst gave reasonable answers, but not as good. The best match is obtained using Hurst simplified solution when lambda = 1.3 x 10{sup -4} m{sup -1}. From the match the cross-sectional area of the aquifer was calculated as 3.6 km{sup 2}. The drawdown was predicted using the Hurst simplified method, and compared with predicted drawdown from a boiling model and an empirical log-log model. A large difference between the models was obtained. The predicted drawdown using the Hurst simplified method falls between the other two. Injection has been considered by defining the net rate as being the production rate minus the injection rate. No thermal of transient effects were taken into account. Prediction using three different net rates shows that the pressure can be maintained using the Hurst simplified method if there is significant fluid reinjection. 32 refs., 44 figs., 2 tabs.

Olsen, G.

1984-06-01T23:59:59.000Z

4

Characterization of Thermal Properties of Depleted Uranium Metal Microspheres  

E-Print Network (OSTI)

Nuclear fuel comes in many forms; oxide fuel is the most commonly used in current reactor systems while metal fuel is a promising fuel type for future reactors due to neutronic performance and increased thermal conductivity. As a key heat transfer parameter, thermal conductivity describes the heat transport properties of a material based upon the density, specific heat, and thermal diffusivity. A material’s ability to transport thermal energy through its structure is a measurable property known as thermal diffusivity; the units for thermal diffusivity are given in area per unit time (e.g., m2/s). Current measurement methods for thermal diffusivity include LASER (or light) Flash Analysis and the hot-wire method. This study examines an approach that combines these previous two methods to characterize the diffusivity of a packed bed of microspheres of depleted uranium (DU) metal, which have a nominal diameter of 250 micrometers. The new apparatus is designated as the Crucible Heater Test Assembly (CHTA), and it induces a radial transient across a packed sample of microspheres then monitors the temperature profile using an array of thermocouples located at different distances from the source of the thermal transient. From the thermocouple data and an accurate time log, the thermal diffusivity of the sample may be calculated. Results indicate that DU microspheres have very low thermal conductivity, relative to solid uranium metal, and rapidly form an oxidation layer. At 500°C, the thermal conductivity of the DU microspheres was 0.431 ± 13% W/m-K compared to approximately 32 W/m-K for solid uranium metal. Characterization of the developed apparatus revealed a method that may be useful for measuring the thermal diffusivity of powders and liquids.

Humrickhouse, Carissa Joy

2012-05-01T23:59:59.000Z

5

Effect of twinning on texture evolution of depleted uranium using a viscoplastic self-consistent model  

Science Conference Proceedings (OSTI)

Ductility and fracture toughness is a major stumbling block in using depleted uranium as a structural material. The ability to correctly model deformation of uranium can be used to create process path methods to improve its structural design ability. The textural evolution of depleted uranium was simulated using a visco-plastic self consistent model and analyzed by comparing pole figures of the simulations and experimental samples. Depleted uranium has the same structure as alpha uranium, which is an orthorhombic phase of uranium. Both deformation slip and twin systems were compared. The VPSC model was chosen to simulate this material because the model encompasses both low-symmetry materials as well as twinning in materials. This is of particular interest since depleted uranium has a high propensity for twinning, which dominates deformation and texture evolution. Simulated results were compared to experimental results to measure the validity of the model. One specific twin system, the {l_brace}176{r_brace}[512] twin, was of specific notice. The VPSC model was used to simulate the influence of this twin on depleted uranium and was compared with a mechanically shocked depleted uranium sample. Under high strain rate shock deformation conditions, the {l_brace}176{r_brace}[512] twin system appears to be a dominant deformation system. By simulating a compression process using the VPSC model with the {l_brace}176{r_brace}[512] twin as the dominant deformation mode, a favorable comparison could be made between the experimental and simulated textures. (authors)

Ho, J.; Garmestani, H. [Georgia Inst. of Technology, Atlanta, GA 30332-0245 (United States); Burrell, R.; Belvin, A. [Y-12 National Security Complex, Oak Ridge, TN (United States); Li, D. [Fundamental and Computational Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA 99352 (United States); McDowell, D. [Woodruff School of Mechanical Engineering, Atlanta, GA 30332-0245 (United States); Rollett, A. [Dept. of Materials Science and Engineering, Carnegie Mellon Univ., Pittsburgh, PA 15213 (United States)

2012-07-01T23:59:59.000Z

6

Depletion and harvesting thermal energy from actuator arm electronics in hard disk drives.  

E-Print Network (OSTI)

??In recent years, thermally assistive magnetic recording (TAMR) has been applied on actuator arm electronics (AE) in hard disk drive (HDD). When HDD operates, temperature… (more)

Wu, Di

2011-01-01T23:59:59.000Z

7

Peak production in an oil depletion model with triangular field profiles  

E-Print Network (OSTI)

Peak production in an oil depletion model with triangular field profiles Dudley Stark School;1 Introduction M. King Hubbert [5] used curve fitting to predict that the peak of oil produc- tion in the U.S.A. would occur between 1965 and 1970. Oil production in the U.S.A. actually peaked in 1970 and has been

Stark, Dudley

8

Thermal Modeling of Hybrid Storage Clusters  

Science Conference Proceedings (OSTI)

There is a lack of thermal models for storage clusters; most existing thermal models do not take into account the utilization of hard drives (HDDs) and solid state disks (SSDs). To address this problem, we build a thermal model for hybrid storage clusters ... Keywords: Cluster, Hybrid, Model, Storage, Thermal

Xunfei Jiang; Maen M. Al Assaf; Ji Zhang; Mohammed I. Alghamdi; Xiaojun Ruan; Tausif Muzaffar; Xiao Qin

2013-09-01T23:59:59.000Z

9

Battery Thermal Modeling and Testing (Presentation)  

DOE Green Energy (OSTI)

This presentation summarizes NREL battery thermal modeling and testing work for the DOE Annual Merit Review, May 9, 2011.

Smith, K.

2011-05-01T23:59:59.000Z

10

Thermal depletion of a geothermal reservoir with both fracture and pore permeability  

DOE Green Energy (OSTI)

A method for estimating the useful lifetime of a reservoir in porous rock where the injection and production wells intersect a fracture system is presented. Equations were derived for the pore-fluid and fracture-fluid temperatures averaged over large regions of the geothermal field. Problems such as incomplete areal sweep and interfingering of cool and hot fluids are ignored. Approximate equations relating average temperatures to the heat flowing from rock to fluid were developed, and their use is justified by comparing the results with solutions of the exact equations. The equations for the temperature decline can be solved quickly. In the model, fractures are characterized by three parameters: aperture w, permeability k/sub fr/, and spacings between fractures D. For certain values of these parameters, cool reinjected fluid in fractures may reach the production wells long before all the warm pore fluid has been tapped, shortening the useful lifetime of the field. The traditional (and important) problems of reservoir engineering, flow rate determination, drawdown, sweep patterns, etc. were ignored. Thus the results are most useful in providing a correction factor which can be applied to lifetime estimates obtained from a detailed simulation of a field assuming porous rock. That correction factor is plotted for clean fractures (k/sub fr/ = w/sup 2//12) as a function of w and D for several lifetime ranges. Small-scale fractures seen in cores from the Salton Sea Geothermal Field are too closely spaced to reduce lifetime estimates. However, large-scale fault systems exist within that field, and they are attractive drilling targets because they produce large flow rates. If large scale faults communicate between injection and production wells, they may reduce the useful lifetime of those wells.

Kasameyer, P.W.; Schroeder, R.C.

1976-08-10T23:59:59.000Z

11

Depleted Uranium  

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

Depleted Uranium Depleted Uranium Depleted Uranium line line Uranium Enrichment Depleted Uranium Health Effects Depleted Uranium Depleted uranium is uranium that has had some of its U-235 content removed. Over the last four decades, large quantities of uranium were processed by gaseous diffusion to produce uranium having a higher concentration of uranium-235 than the 0.72% that occurs naturally (called "enriched" uranium) for use in U.S. national defense and civilian applications. "Depleted" uranium is also a product of the enrichment process. However, depleted uranium has been stripped of some of its natural uranium-235 content. Most of the Department of Energy's (DOE) depleted uranium inventory contains between 0.2 to 0.4 weight-percent uranium-235, well

12

Econometric Modelling of World Oil Supplies: Terminal Price and the Time to Depletion  

E-Print Network (OSTI)

This paper develops a novel approach by which to identify the price of oil at the time of depletion; the so-called "terminal price " of oil. It is shown that while the terminal price is independent of both GDP growth and the price elasticity of energy demand, it is dependent on the world real interest rate and the total life-time stock of oil resources, as well as on the marginal extraction and scarcity cost parameters. The theoretical predictions of this model are evaluated using data on the cost of extraction, cumulative production, and proven reserves. The predicted terminal prices seem sensible for a range of parameters and variables, as illustrated by the sensitivity analysis. Using the terminal price of oil, we calculate the time to depletion, and determine the extraction and price pro…les over the life-time of the resource. The extraction pro…les generated seem to be in line with the actual production and the predicted prices are generally in line with those currently observed.

Kamiar Mohaddes

2013-01-01T23:59:59.000Z

13

The IAEA Coordinated Research Program on HTGR Reactor Physics, Thermal-hydraulics and Depletion Uncertainty Analysis: Description of the Benchmark Test Cases and Phases  

SciTech Connect

The continued development of High Temperature Gas Cooled Reactors (HTGRs) requires verification of design and safety features with reliable high fidelity physics models and robust, efficient, and accurate codes. The uncertainties in the HTR analysis tools are today typically assessed with sensitivity analysis and then a few important input uncertainties (typically based on a PIRT process) are varied in the analysis to find a spread in the parameter of importance. However, one wish to apply a more fundamental approach to determine the predictive capability and accuracies of coupled neutronics/thermal-hydraulics and depletion simulations used for reactor design and safety assessment. Today there is a broader acceptance of the use of uncertainty analysis even in safety studies and it has been accepted by regulators in some cases to replace the traditional conservative analysis. Finally, there is also a renewed focus in supplying reliable covariance data (nuclear data uncertainties) that can then be used in uncertainty methods. Uncertainty and sensitivity studies are therefore becoming an essential component of any significant effort in data and simulation improvement. In order to address uncertainty in analysis and methods in the HTGR community the IAEA launched a Coordinated Research Project (CRP) on the HTGR Uncertainty Analysis in Modelling early in 2012. The project is built on the experience of the OECD/NEA Light Water Reactor (LWR) Uncertainty Analysis in Best-Estimate Modelling (UAM) benchmark activity, but focuses specifically on the peculiarities of HTGR designs and its simulation requirements. Two benchmark problems were defined with the prismatic type design represented by the MHTGR-350 design from General Atomics (GA) while a 250 MW modular pebble bed design, similar to the INET (China) and indirect-cycle PBMR (South Africa) designs are also included. In the paper more detail on the benchmark cases, the different specific phases and tasks and the latest status and plans are presented.

Frederik Reitsma; Gerhard Strydom; Bismark Tyobeka; Kostadin Ivanov

2012-10-01T23:59:59.000Z

14

Integrated Chemical, Thermal, Mechanical and Hydrological Modeling...  

Open Energy Info (EERE)

489,476 1,602,500 Retrieved from "http:en.openei.orgwindex.php?titleIntegratedChemical,Thermal,MechanicalandHydrologicalModeling&oldid313283" Category:...

15

IDENTIFICATION OF AN {sup 84}Sr-DEPLETED CARRIER IN PRIMITIVE METEORITES AND IMPLICATIONS FOR THERMAL PROCESSING IN THE SOLAR PROTOPLANETARY DISK  

SciTech Connect

The existence of correlated nucleosynthetic heterogeneities in solar system reservoirs is now well demonstrated for numerous nuclides. However, it has proven difficult to discriminate between the two disparate processes that can explain such correlated variability: incomplete mixing of presolar material or secondary processing of a well-mixed disk. Using stepwise acid-leaching of the Ivuna CI-chondrite, we show that unlike other nuclides such as {sup 54}Cr and {sup 50}Ti, Sr-isotope variability is the result of a carrier depleted in {sup 84}Sr. The carrier is most likely presolar SiC, which is known to have both high Sr-concentrations relative to solar abundances and extremely depleted {sup 84}Sr compositions. Thus, variability in {sup 84}Sr in meteorites and their components can be attributed to varying contributions from presolar SiC. The observed {sup 84}Sr excesses in calcium-aluminum refractory inclusions (CAIs) suggest their formation from an SiC-free gaseous reservoir, whereas the {sup 84}Sr depletions present in differentiated meteorites require their formation from material with an increased concentration of SiC relative to CI chondrites. The presence of a positive correlation between {sup 84}Sr and {sup 54}Cr, despite being hosted in carriers of negative and positive anomalies, respectively, is not compatible with incomplete mixing of presolar material but instead suggests that the solar system's nucleosynthetic heterogeneity reflects selective thermal processing of dust. Based on vaporization experiments of SiC under nebular conditions, the lack of SiC material in the CAI-forming gas inferred from our data requires that the duration of thermal processing of dust resulting in the vaporization of CAI precursors was extremely short-lived, possibly lasting only hours to days.

Paton, Chad; Schiller, Martin; Bizzarro, Martin, E-mail: chadpaton@gmail.com, E-mail: schiller@snm.ku.dk, E-mail: bizzarro@snm.ku.dk [Centre for Star and Planet Formation, Natural History Museum of Denmark, University of Copenhagen, Copenhagen DK-1350 (Denmark)

2013-02-01T23:59:59.000Z

16

Quasi-Lagrangian Models of Nascent Thermals  

Science Conference Proceedings (OSTI)

Thermals are modeled by considering their boundaries as self-advecting vortex sheets. Both slab-symmetric and axisymmetiic geometries are considered. Discussion is restricted to the case of a neutral environment, and turbulent processes are not ...

Sandro Rambaldi; David A. Randall

1981-09-01T23:59:59.000Z

17

Model Predictive Control of Thermal Energy Storage in Building...  

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

Model Predictive Control of Thermal Energy Storage in Building Cooling Systems Title Model Predictive Control of Thermal Energy Storage in Building Cooling Systems Publication Type...

18

Debris Thermal Hydraulics Modeling of QUENCH Experiments  

SciTech Connect

Porous debris formation and behavior in QUENCH experiments (QUENCH-02, QUENCH-03) plays a considerable role and its adequate modeling is important for thermal analysis. This work is aimed to the development of a numerical module which is able to model thermal hydraulics and heat transfer phenomena occurring during the high-temperature stage of severe accident with the formation of debris region and molten pool. The original approach for debris evolution is developed from classical principles using a set of parameters including debris porosity; average particle diameter; temperatures and mass fractions of solid, liquid and gas phases; specific interface areas between different phases; effective thermal conductivity of each phase, including radiative heat conductivity; mass and energy fluxes through the interfaces. The debris model is based on the system of continuity, momentum and energy conservation equations, which consider the dynamics of volume-averaged velocities and temperatures of fluid, solid and gaseous phases of porous debris. The different mechanisms of debris formation are considered, including degradation of fuel rods according to temperature criteria, taking into consideration some correlations between rod layers thicknesses; degradation of rod layer structure due to thermal expansion of melted materials inside intact rod cladding; debris formation due to sharp temperature drop of previously melted material due to reflood; and transition to debris of material from elements lying above. The porous debris model was implemented to best estimate numerical code RATEG/SVECHA/HEFEST developed for modeling thermal hydraulics and severe accident phenomena in a reactor. The model is used for calculation of QUENCH experiments. The results obtained by the model are compared to experimental data concerning different aspects of thermal behavior: thermal hydraulics of porous debris, radiative heat transfer in a porous medium, the generalized melting and refreezing behavior of materials, hydrogen production. (authors)

Kisselev, Arcadi E.; Kobelev, Gennadii V.; Strizhov, Valerii F.; Vasiliev, Alexander D. [Nuclear Safety Institute - IBRAE, 52 Bolshaya Tulskaya Ulitsa, Moscow, 113191 (Russian Federation)

2006-07-01T23:59:59.000Z

19

Rigorous Simulation of X-Ray Thermal Diffuse Scattering  

Science Conference Proceedings (OSTI)

In-Situ Neutron Diffraction and Crystal Plasticity Modeling of a-Uranium · In-Situ Studies of the ... Thermal Residual Stresses and Strains in Depleted Uranium.

20

Modeling Thermal Fatigue in CPV Cell Assemblies (Presentation)  

DOE Green Energy (OSTI)

This presentation outlines the modeling of thermal fatigue in concentrating photovoltaic (CPV) assemblies.

Bosco, N.; Panchagade, D.; Kurtz, S.

2011-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "thermal depletion model" 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

Thermal conductivity modeling of building façade materials  

Science Conference Proceedings (OSTI)

An experimental research has been conducted to assess the thermo-physical properties of three building materials in both dry and moist state: beech wood, autoclaved aerated concrete and brick. The objectives of the paper envisage the measurement of the ... Keywords: building materials, contact temperature, determining method, finite element, numerical modeling, thermal conductivity

Monica Chereches; Nelu-Cristian Chereches; Catalin Popovici

2010-04-01T23:59:59.000Z

22

Thermal modeling of W rod armor.  

Science Conference Proceedings (OSTI)

Sandia has developed and tested mockups armored with W rods over the last decade and pioneered the initial development of W rod armor for International Thermonuclear Experimental Reactor (ITER) in the 1990's. We have also developed 2D and 3D thermal and stress models of W rod-armored plasma facing components (PFCs) and test mockups and are applying the models to both short pulses, i.e. edge localized modes (ELMs), and thermal performance in steady state for applications in C-MOD, DiMES testing and ITER. This paper briefly describes the 2D and 3D models and their applications with emphasis on modeling for an ongoing test program that simulates repeated heat loads from ITER ELMs.

Nygren, Richard Einar

2004-09-01T23:59:59.000Z

23

A transient model for data center thermal prediction  

Science Conference Proceedings (OSTI)

Fast thermal maps are a crucial component for many green data center design techniques. However, most state of the art work on thermal mapping ignores critical temporal aspects of thermal behavior and relies on modeling assumptions, such as the steady ...

Michael Jonas; Rose Robin Gilbert; Joshua Ferguson; Georgios Varsamopoulos; Sandeep K. S. Gupta

2012-06-01T23:59:59.000Z

24

Charge Depleting:  

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

0.5 seconds 0.5 seconds Acceleration 1/4 Mile Time: 18.6 seconds Maximum Speed: 83.2 MPH Acceleration 1 Mile Maximum Speed: 100.6 MPH Charge Sustaining: Acceleration 0-60 MPH Time: 10.6 seconds Acceleration 1/4 Mile Time: 18.6 seconds Maximum Speed: 82.8 MPH Acceleration 1 Mile Maximum Speed: 101.9 MPH Brake Test @ 60 MPH Distance Required: 145.1 ft UDDS Fuel Economy 6 HWFET Fuel Economy 6,10 Distance (miles) Fuel Economy (mpg) AC Energy Consumed (kWh) 7 Distance (miles) Fuel Economy (mpg) AC Energy Consumed (kWh) 7 10 118.5 2.85 10 53.0 1.80 20 116.8 5.49 20 56.6 3.37 40 116.0 10.50 40 58.0 6.38 60 90.7 11.34 60 55.3 9.48 80 76.6 11.34 80 51.4 11.11 100 68.0 11.34 100 47.2 11.13 200 50.9 11.34 200 38.7 11.13 Fuel Economy with A/C Off 1 Cold Start Charge Depleting 2 : Fuel Economy: 119.7 MPG AC kWh Consumed 7 : 0.282 kWh/mi Charge Depleting

25

Modeling thermal comfort in stratified environments  

E-Print Network (OSTI)

Arens E. , and Wang D. 2004. "Thermal sensation and comfortin transient non-uniform thermal environments", European7730, 1994, Moderate Thermal Environments – Determination of

Zhang, H.; Huizenga, C.; Arens, Edward A; Yu, T.

2005-01-01T23:59:59.000Z

26

Modeling of the thermal degradation of structural wood ...  

Science Conference Proceedings (OSTI)

... 37. Koufopanos C, Papayannakos N. Modeling the pyrolysis of biomass particles: studies on kinetics, thermal and heat transfer effects. ...

2005-02-01T23:59:59.000Z

27

Battery Thermal Management System Design Modeling (Presentation)  

DOE Green Energy (OSTI)

Presents the objectives and motivations for a battery thermal management vehicle system design study.

Kim, G-H.; Pesaran, A.

2006-10-01T23:59:59.000Z

28

Econometric Modelling of World Oil Supplies: Terminal Price and the Time to Depletion  

E-Print Network (OSTI)

demand, it is dependent on the world real interest rate and the total life-time stock of oil resources, as well as on the marginal extraction and scarcity cost parameters. The theoretical predictions of this model are evaluated using data on the cost...

Mohaddes, Kamiar

2012-03-02T23:59:59.000Z

29

Modeling and Optimizing the Thermal Stress Distribution in a ...  

Science Conference Proceedings (OSTI)

Conference Tools for Materials Science & Technology 2012 ... Presentation Title, Modeling and Optimizing the Thermal Stress Distribution in a Plasma Spray System for ... and analyzed for an applied thermal load in COMSOL® Multiphysics®.

30

Modeling studies of cold water injection into fluid-depleted, vapor-dominated geothermal reservoirs  

DOE Green Energy (OSTI)

The physical processes involved in cold water injection into a ''superheated'' fractured reservoir are not yet fully understood, and this insufficient knowledge of the fundamental mechanisms limits the possibility of forecasting future resevoir behavior and optimizing the heat extraction process. Numerical simulation can be a very effective tool in the study of the complex phenomena involved, allowing a rapid examination of different situations and conditions, a systematic investigation of the effects of various parameters on reservoir performance, and some insight into long term behavior. We have performed simulation experiments on simple one-dimensional, porous and fractured reservoir models in order to study the migration of injected water, thermodynamic conditions in the boiling zone, heat extraction, and vapor generation. A two-dimensional radial porous medium model, with some characteristics typical of the high productivity zones of Larderello, has also been applied for studying the evolution of the shape and the thermodynamic conditions of the injection plume in the presence of gravity, reservoir heterogeneities and anisotropy.

Calore, C.; Pruess, K.; Celati, R.

1986-01-01T23:59:59.000Z

31

An Empirical Model of UO2 Thermal Conductivity Based on Laser Flash Measurements of Thermal Diffusivity  

Science Conference Proceedings (OSTI)

Thermal conductivity of irradiated fuel materials, which can be derived from measured thermal diffusivity (TD), is a key consideration in thermal performance and design of a fuel rod. However, without interpretation, the measured TD data cannot be used directly to calculate fuel temperatures during irradiation. This report provides such interpretation and presents an empirical model for the degradation of UO2 thermal conductivity with burn-up.

1998-10-07T23:59:59.000Z

32

Depleted Uranium Hexafluoride Management  

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

OFFICE OF DEPLETED URANIUM HEXAFLUORIDE MANAGEMENT Issuance Of Final Report On Preconceptual Designs For Depleted Uranium Hexafluoride Conversion Plants The Department of Energy...

33

Battery Thermal Management System Design Modeling  

SciTech Connect

Looks at the impact of cooling strategies with air and both direct and indirect liquid cooling for battery thermal management.

Pesaran, A.; Kim, G. H.

2006-11-01T23:59:59.000Z

34

Geothermal: Sponsored by OSTI -- Modeling Thermally Induced Failure...  

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

GEOTHERMAL TECHNOLOGIES LEGACY COLLECTION - Sponsored by OSTI -- Modeling Thermally Induced Failure of Brittle Geomaterials Geothermal Technologies Legacy Collection HelpFAQ |...

35

Coupled Thermal-Hydrological-Mechanical-Chemical Model and Experiments...  

Open Energy Info (EERE)

of Applications for Research, Development and Analysis of Geothermal Technologies Project Type Topic 2 Integrated Chemical, Thermal, Mechanical and Hydrological Modeling...

36

Modelling Concentrating Solar Power with Thermal Energy Storage...  

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

Modelling Concentrating Solar Power with Thermal Energy Storage for Integration Studies Marissa Hummon 3 rd International Solar Power Integration Workshop October 20-22, 2013...

37

TransForum v2n4 - Underhood Thermal Modeling  

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

UNDERHOOD THERMAL MODELING UNDERGOES BIG IMPROVEMENTS Argonne and its partners simulate intense heat in confined spaces A stream of air roars through narrow openings into...

38

Thermal-Mechanical Fatigue Life Model for Coated Superalloy ...  

Science Conference Proceedings (OSTI)

in an aggressive combustion gas environment. Coating ..... M.I. Wood and G.F. Harrison, "Modeling The Deformation Of Coated. Superalloys Under Thermal ...

39

Improving Battery Design with Electro-Thermal Modeling  

DOE Green Energy (OSTI)

Temperature greatly affects the performance and life of batteries in electric and hybrid vehicles under real driving conditions, so increased attention is being paid to battery thermal management. Sophisticated electrochemical models and finite element analysis tools are available for predicting the thermal performance of batteries, but each has limitations. In this study we describe an electro-thermal finite element approach that predicts the thermal performance of a cell or module with realistic geometry, material properties, loads, and boundary conditions.

Pesaran, A.; Vlahinos, A.; Bharathan, D.; Kim, G.-H.; Duong, T.

2005-08-01T23:59:59.000Z

40

Electro-Thermal Modeling to Improve Battery Design: Preprint  

DOE Green Energy (OSTI)

Operating temperature greatly affects the performance and life of batteries in electric and hybrid electric vehicles (HEVs). Increased attention is necessary to battery thermal management. Electrochemical models and finite element analysis tools are available for predicting the thermal performance of batteries, but each has limitations. This study describes an electro-thermal finite element approach that predicts the thermal performance of a battery cell or module with realistic geometry.

Bharathan, D.; Pesaran, A.; Kim, G.; Vlahinos, A.

2005-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "thermal depletion model" 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

Improving Battery Design with Electro-Thermal Modeling  

DOE Green Energy (OSTI)

Operating temperature greatly affects the performance and life of batteries in electric and hybrid vehicles. Increased attention is necessary to battery thermal management. Electrochemical models and finite element analysis tools are available for predicting the thermal performance of batteries, but each has limitations. In this study we describe an electro-thermal finite element approach that predicts the thermal performance of a cell or module with realistic geometry. To illustrate the process, we simulated the thermal performance of two generations of Panasonic prismatic nickel-metal-hydride modules used in the Toyota Prius. The model showed why the new generation of Panasonic modules had better thermal performance. Thermal images from two battery modules under constant current discharge indicate that the model predicts the experimental trend reasonably well.

Bharathan, D.; Pesaran, A.; Vlahinos, A.; Kim, G.-H.

2005-01-01T23:59:59.000Z

42

Depleted Uranium Health Effects  

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

Depleted Uranium Health Effects Depleted Uranium Health Effects Depleted Uranium line line Uranium Enrichment Depleted Uranium Health Effects Depleted Uranium Health Effects Discussion of health effects of external exposure, ingestion, and inhalation of depleted uranium. Depleted uranium is not a significant health hazard unless it is taken into the body. External exposure to radiation from depleted uranium is generally not a major concern because the alpha particles emitted by its isotopes travel only a few centimeters in air or can be stopped by a sheet of paper. Also, the uranium-235 that remains in depleted uranium emits only a small amount of low-energy gamma radiation. However, if allowed to enter the body, depleted uranium, like natural uranium, has the potential for both chemical and radiological toxicity with the two important target organs

43

Experimental and analytic studies to model kinetics and mass transport of carbon dioxide sequstration in depleted carbonate reservoirs  

SciTech Connect

There is undeniable evidence that concentration of carbon dioxide in the atmosphere is rising at an increasingly rapid rate primarily as the result of burning fossil fuels. Although the debate continues, most of the scientific community believes that higher levels of atmospheric CO2 will lead to a significant warming of the Earth’s climate and that there is already evidence that this is occurring. There are two ways to ameliorate this problem. One is to significantly reduce production of CO2, which is primarily a political-economic problem, and the other is to remove CO2 from emissions and/or the atmosphere and find some way to sequester it. Several possible ways to sequester CO2 are under investigation or have been suggested. These include removal by chemical reaction, deep seabed disposal, and pumping supercritical CO2 into various subsurface environments. Sequestration of carbon dioxide in depleted gas reservoirs appears to be a viable option, with a possible economic spin-off from the recovery of significant gas reserves. At the elevated temperatures and pressures encountered in reservoirs, carbon dioxide behaves as a supercritical fluid. Under these conditions, little was known regarding the, diffusion of carbon dioxide in natural gas, and displacement of natural gas by carbon dioxide. A major objective of this research was to obtain the necessary data to model these processes. Also, the added CO2 will react with reservoir waters that are often chemically complex high ionic strength brines making them more acidic. This can result in the dissolution of calcium carbonate (calcite) that is a common host rock or sandstone cement in reservoirs and lead to potentially serious problems for CO2 injection and the integrity of the reservoir. It was consequently a second major objective of this project to determine calcite solubility and dissolution kinetics in solutions representative of subsurface brines and produce a general dissolution rate equation. Both objectives were accomplished. Reservoir simulations indicated a large amount of CO2 would be sequestered, with the amount depending on reservoir water saturation. Simulation results also indicate a significant amount of natural gas could be produced. For an 80-acre pattern, natural gas production was calculated to be 3.2 BSCF or 63% of remaining gas-in-place for 30% reservoir water saturation. Gas revenues would help defray the cost of CO2 sequestration. Therefore, CO2 sequestration in depleted gas reservoirs appears to be a win-win technology. Considerable effort went into testing and refining the ability to predict calcite solubility in brines using a Pitzer-equation based computer model, with particular difficulties being encountered in solutions with high dissolved calcium concentrations. After that was accomplished, calcite dissolution kinetics were determined a wide range of brine compositions both including and not including potential inhibitors from 25 to 83 oC and a CO2 partial pressure from 0.1 to 1 atm. The reaction was found to be first order for undersaturations of 0.2 to ~1 and was surface controlled. The rate constant was fit to a multiple regression model, thus making it possible to predict calcite dissolution rates over a wide range of solution compositions, partial pressures of CO2 and temperature. Results indicate that equilibrium is likely to be reached relatively quickly in front of an advancing supercritical CO2 fluid.

Morse, John W; Mamora, Daulat

2006-10-31T23:59:59.000Z

44

A model reduction approach for constructing compact dynamic thermal models of IGBT-modules of inverters  

Science Conference Proceedings (OSTI)

This paper presents a model reduction approach for constructing lumped RC thermal networks of IGBT-modules of inverters for which heat and subsequent temperature increases vary with time on different scales ranging from nanosecond to second. It was observed ... Keywords: Compact thermal modelling, Electro-thermal simulation, IGBT-modules, Inverters, Thermal analysis

J. Antonios; N. Ginot; C. Batard; Y. Scudeller; M. Machmoum

2012-06-01T23:59:59.000Z

45

Development of a PMV-based thermal comfort modelling  

Science Conference Proceedings (OSTI)

This paper concentrates on the modelling development for a PMV-based thermal comfort system. Operators can define their own expression towards the surroundings by inserting the respective value of PMV and the system will generate the compressor and fan ... Keywords: climatic modelling, predicted mean vote (PMV), thermal comfort

Shazmin Aniza Abdul Shukor; Karl Kohlhof; Zul Azhar Zahid Jamal

2007-05-01T23:59:59.000Z

46

The Thermal Balance of the NCAR Community Climate Model  

Science Conference Proceedings (OSTI)

The thermal balance of the NCAR Community Climate Model is examined using the zonally averaged temperature tendency equation of the model. The perpetual January and perpetual July control simulations are used to determine the relative importance ...

Byron A. Boville

1985-04-01T23:59:59.000Z

47

Inverse Modeling for Determination of Thermal Properties of the ...  

Science Conference Proceedings (OSTI)

Thermal properties of ceramic shell depend on shell composition and fabrication ... Mathematical Modeling of a Compressible Oxygen Jet Interacting with a Free ... Multi-Physics Modeling of Molten Salt Transport in Solid Oxide Membrane ...

48

Analytical-Numerical Modeling Of Komatiite Lava Emplacement And Thermal  

Open Energy Info (EERE)

Analytical-Numerical Modeling Of Komatiite Lava Emplacement And Thermal Analytical-Numerical Modeling Of Komatiite Lava Emplacement And Thermal Erosion At Perseverance, Western Australia Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Analytical-Numerical Modeling Of Komatiite Lava Emplacement And Thermal Erosion At Perseverance, Western Australia Details Activities (0) Areas (0) Regions (0) Abstract: We have applied a thermal-fluid dynamic-geochemical model to investigate the emplacement and erosional potential of Archean komatiite flows at Perseverance, Western Australia. Perseverance has been proposed as a site of large-scale thermal erosion by large-volume komatiite eruption(s), resulting in a 100-150-m-deep lava channel containing one of the world's largest komatiite-hosted Fe-Ni-Cu-(PGE) sulfide deposits. Using

49

Modeling The Potential For Thermal Concentrating Solar Power Technologies  

SciTech Connect

In this paper we explore the tradeoffs between thermal storage capacity, cost, and other system parameters in order to examine possible evolutionary pathways for thermal Concen-trating Solar Power (CSP) technologies. A representation of CSP performance that is suit-able for incorporation into economic modeling tools is developed. We find that, as the fraction of electricity supplied by CSP technologies grows, the application of thermal CSP technologies might progress from current hybrid plants, to plants with a modest amount of thermal storage, and potentially even to plants with sufficient thermal storage to provide base load generation capacity. The representation of CSP cost and performance developed here was implemented in the ObjECTS MiniCAM long-term integrated assessment model. Datasets for global solar resource characteristics as applied to CSP technology were also developed. The regional and global potential of thermal CSP technologies is examined.

Zhang, Yabei; Smith, Steven J.; Kyle, G. Page; Stackhouse, Jr., Paul W.

2010-10-25T23:59:59.000Z

50

FAQ 23-How much depleted uranium -- including depleted uranium...  

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

is stored in the United States? How much depleted uranium -- including depleted uranium hexafluoride -- is stored in the United States? In addition to the depleted uranium stored...

51

Transformer Thermal Modeling: Improving Reliability Using Data Quality Control  

E-Print Network (OSTI)

1 Transformer Thermal Modeling: Improving Reliability Using Data Quality Control Daniel J. Tylavsky--Eventually all large transformers will be dynamically loaded using models updated regularly from field measured data. Models obtained from measured data give more accurate results than models based on transformer

52

Thermal Modeling and Feedback Requirements for LIFE Neutronic Simulations  

Science Conference Proceedings (OSTI)

An initial study is performed to determine how temperature considerations affect LIFE neutronic simulations. Among other figures of merit, the isotopic mass accumulation, thermal power, tritium breeding, and criticality are analyzed. Possible fidelities of thermal modeling and degrees of coupling are explored. Lessons learned from switching and modifying nuclear datasets is communicated.

Seifried, J E

2009-07-15T23:59:59.000Z

53

RELAP5 model of the high flux isotope reactor with low enriched fuel thermal flux profiles  

Science Conference Proceedings (OSTI)

The High Flux Isotope Reactor (HFIR) currently uses highly enriched uranium (HEU) fabricated into involute-shaped fuel plates. It is desired that HFIR be able to use low enriched uranium (LEU) fuel while preserving the current performance capability for its diverse missions in material irradiation studies, isotope production, and the use of neutron beam lines for basic research. Preliminary neutronics and depletion simulations of HFIR with LEU fuel have arrived to feasible fuel loadings that maintain the neutronics performance of the reactor. This article illustrates preliminary models developed for the analysis of the thermal-hydraulic characteristics of the LEU core to ensure safe operation of the reactor. The beginning of life (BOL) LEU thermal flux profile has been modeled in RELAP5 to facilitate steady state simulation of the core cooling, and of anticipated and unanticipated transients. Steady state results are presented to validate the new thermal power profile inputs. A power ramp, slow depressurization at the outlet, and flow coast down transients are also evaluated. (authors)

Banfield, J.; Mervin, B.; Hart, S.; Ritchie, J.; Walker, S.; Ruggles, A.; Maldonado, G. I. [Dept. of Nuclear Engineering, Univ. of Tennessee Knoxville, Knoxville, TN 37996-2300 (United States)

2012-07-01T23:59:59.000Z

54

NREL: Vehicle Ancillary Loads Reduction - Thermal Comfort Model  

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

Comfort Model Comfort Model Photo of human testing to determine thermal comfort perception data. Photo of human testing to determine thermal comfort perception data. Working with researchers at the University of California, Berkeley, our team at NREL developed an empirical model of people's temperature sensation (hot/cold) as well as perceptions (comfortable/uncomfortable) in a transient non-homogeneous environment. The model predicts sensation and comfort locally (at specific points on the body) as well as globally (overall). The university performed more than 100 tests on human test subjects in a controlled environmental chamber under a range of steady state and transient thermal conditions. Participants subjectively recorded their thermal comfort on a simple form. Core and local skin temperature data was

55

Electrical, Frequency and Thermal Measurement and Modelling of Supercapacitor Performance  

E-Print Network (OSTI)

Electrical, Frequency and Thermal Measurement and Modelling of Supercapacitor Performance Yasser--This paper presents an evaluation of commercial supercapacitors performance (ESR, C, self-discharge, Pmax, Emax, coulumbic efficiency, etc), under different conditions. Characterization of supercapacitor

Paris-Sud XI, Université de

56

Comprehensive Model Simulation of Thermal Tides in the Martian Atmosphere  

Science Conference Proceedings (OSTI)

This paper discusses the thermotidal oscillations in simulations performed with a newly developed comprehensive general circulation model of the Martian atmosphere. With reasonable assumptions about the effective thermal inertia of the planetary ...

R. John Wilson; Kevin Hamilton

1996-05-01T23:59:59.000Z

57

Asymmetric X-Ray Line Broadening: From the Composite Model to ...  

Science Conference Proceedings (OSTI)

In-Situ Neutron Diffraction and Crystal Plasticity Modeling of a-Uranium · In-Situ Studies of the ... Thermal Residual Stresses and Strains in Depleted Uranium.

58

Automotive Underhood Thermal Management Analysis Using 3-D Coupled Thermal-Hydrodynamic Computer Models: Thermal Radiation Modeling  

SciTech Connect

The goal of the radiation modeling effort was to develop and implement a radiation algorithm that is fast and accurate for the underhood environment. As part of this CRADA, a net-radiation model was chosen to simulate radiative heat transfer in an underhood of a car. The assumptions (diffuse-gray and uniform radiative properties in each element) reduce the problem tremendously and all the view factors for radiation thermal calculations can be calculated once and for all at the beginning of the simulation. The cost for online integration of heat exchanges due to radiation is found to be less than 15% of the baseline CHAD code and thus very manageable. The off-line view factor calculation is constructed to be very modular and has been completely integrated to read CHAD grid files and the output from this code can be read into the latest version of CHAD. Further integration has to be performed to accomplish the same with STAR-CD. The main outcome of this effort is to obtain a highly scalable and portable simulation capability to model view factors for underhood environment (for e.g. a view factor calculation which took 14 hours on a single processor only took 14 minutes on 64 processors). The code has also been validated using a simple test case where analytical solutions are available. This simulation capability gives underhood designers in the automotive companies the ability to account for thermal radiation - which usually is critical in the underhood environment and also turns out to be one of the most computationally expensive components of underhood simulations. This report starts off with the original work plan as elucidated in the proposal in section B. This is followed by Technical work plan to accomplish the goals of the project in section C. In section D, background to the current work is provided with references to the previous efforts this project leverages on. The results are discussed in section 1E. This report ends with conclusions and future scope of work in section F.

Pannala, S.; D'Azevedo, E.; Zacharia, T.

2002-02-26T23:59:59.000Z

59

Assessing the reliability of linear dynamic transformer thermal modelling  

E-Print Network (OSTI)

Assessing the reliability of linear dynamic transformer thermal modelling X. Mao, D.J. Tylavsky and G.A. McCulla Abstract: Improving the utilisation of transformers requires that the hot-spot and top. An alternative method for assessing transformer model reliability is provided. 1 Introduction The maximally

60

Near and far field models of external fluid mechanics of Ocean Thermal Energy Conversion (OTEC) power plants  

E-Print Network (OSTI)

The world is facing the challenge of finding new renewable sources of energy - first, in response to fossil fuel reserve depletion, and second, to reduce greenhouse gas emissions. Ocean Thermal Energy Conversion (OTEC) can ...

Rodríguez Buño, Mariana

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "thermal depletion model" 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

Testing Climate Models Using Thermal Infrared Spectra  

Science Conference Proceedings (OSTI)

An approach to test climate models with observations is presented. In this approach, it is possible to directly observe the longwave feedbacks of the climate system in time series of annual average outgoing longwave spectra. Tropospheric ...

Stephen Leroy; James Anderson; John Dykema; Richard Goody

2008-05-01T23:59:59.000Z

62

Modeling Thermal Fatigue in CPV Cell Assemblies: Preprint  

DOE Green Energy (OSTI)

A finite element model has been created to quantify the thermal fatigue damage of the CPV die attach. Simulations are used to compare to results of empirical thermal fatigue equations originally developed for accelerated chamber cycling. While the empirical equations show promise when extrapolated to the lower temperature cycles characteristic of weather-induced temperature changes in the CPV die attach, it is demonstrated that their damage does not accumulate linearly: the damage a particular cycle contributes depends on the preceding cycles. Simulations of modeled CPV cell temperature histories provided for direct comparison of the FEM and empirical methods, and for calculation of equivalent times provided by standard accelerated test sequences.

Bosco, N.; Silverman, T. J.; Kurtz, S.

2011-07-01T23:59:59.000Z

63

A Method for Serial Tissue Processing and Parallel Analysis of Aberrant Crypt Morphology, Mucin Depletion, and Beta-Catenin Staining in an Experimental Model  

E-Print Network (OSTI)

# The Author(s) 2010. This article is published with open access at Springerlink.com Abstract The use of architectural and morphological characteristics of cells for establishing prognostic indicators by which individual pathologies are assigned grade and stage is a well-accepted practice. Advances in automated micro- and macroscopic image acquisition and digital image analysis have created new opportunities in the field of prognostic assessment; but, one area in experimental pathology, animal models for colon cancer, has not taken advantage of these opportunities. This situation is primarily due to the methods available to evaluate the colon of the rodent for the presence of premalignant and malignant pathologies. We report a new method for the excision and processing of the entire colon of the rat and illustrate how this procedure permitted the quantitative assessment of aberrant crypt foci (ACF), a premalignant colon pathology, for characteristics consistent with progression to malignancy. ACF were detected by methylene blue staining and subjected to quantitative morphometric analysis. Colons were then restained with high iron diamine–alcian blue for assessment of mucin depletion using an image overlay to associate morphometric data with mucin depletion. The subsequent evaluation of ACF for beta-catenin staining is also demonstrated. The methods described are particularly relevant to the screening of compounds for cancer chemopreventive activity. Electronic supplementary material The online version of this article (doi:10.1007/s12575-010-9032-x) contains supplementary material, which is available to authorized users.

Of Colon Carcinogenesis; John N. Mcginley; Matthew D. Thompson; Henry J. Thompson

2010-01-01T23:59:59.000Z

64

Battery depletion monitor  

SciTech Connect

A cmos inverter is used to compare pacemaker battery voltage to a referenced voltage. When the reference voltage exceeds the measured battery voltage, the inverter changes state to indicate battery depletion.

Lee, Y.S.

1982-01-26T23:59:59.000Z

65

Hybrid Model of Existing Buildings for Transient Thermal Performance Estimation  

E-Print Network (OSTI)

Building level energy models are important to provide accurate prediction of energy consumption for building performance diagnosis and energy efficiency assessment of retrofitting alternatives for building performance upgrading. Simplified but physically meaningful models for existing buildings are preferable for practical applications. In this study, a hybrid building model is developed to describe building system for thermal performance prediction at building level. The model includes two parts. One part is the detailed physical models, which are the CTF models of building envelopes based on the easily available coincident detailed physical properties. The other part is the simplified 2R2C model for building internal mass, whose parameters are estimated and optimized using short-term monitored operation data. A genetic algorithm estimator is developed to optimize these parameters. The parameter optimization of the simplified model and the hybrid building model are validated in a high-rise commercial office building under various weather conditions.

Xu, X.; Wang, S.

2006-01-01T23:59:59.000Z

66

Depleted uranium valuation  

SciTech Connect

The following uses for depleted uranium were examined to determine its value: a substitute for lead in shielding applications, feed material in gaseous diffusion enrichment facilities, feed material for an advanced enrichment concept, Mixed Oxide (MOx) diluent and blanket material in LMFBRs, and fertile material in LMFBR systems. A range of depleted uranium values was calculated for each of these applications. The sensitivity of these values to analysis assumptions is discussed. 9 tables.

Lewallen, M.A.; White, M.K.; Jenquin, U.P.

1979-04-01T23:59:59.000Z

67

Thermohydraulic modeling of nuclear thermal rockets: The KLAXON code  

DOE Green Energy (OSTI)

The hydrogen flow from the storage tanks, through the reactor core, and out the nozzle of a Nuclear Thermal Rocket is an integral design consideration. To provide an analysis and design tool for this phenomenon, the KLAXON code is being developed. A shock-capturing numerical methodology is used to model the gas flow (the Harten, Lax, and van Leer method, as implemented by Einfeldt). Preliminary results of modeling the flow through the reactor core and nozzle are given in this paper.

Hall, M.L.; Rider, W.J.; Cappiello, M.W.

1992-07-01T23:59:59.000Z

68

Lumped-parameter fuel rod model for rapid thermal transients  

SciTech Connect

The thermal behavior of fuel rods during simulated accident conditions is extremely sensitive to the heat transfer coefficient which is, in turn, very sensitive to the cladding surface temperature and the fluid conditions. The development of a semianalytical, lumped-parameter fuel rod model which is intended to provide accurate calculations, in a minimum amount of computer time, of the thermal response of fuel rods during a simulated loss-of-coolant accident is described. The results show good agreement with calculations from a comprehensive fuel-rod code (FRAP-T) currently in use at Aerojet Nuclear Company. (auth)

Perkins, K.R.; Ramshaw, J.D.

1975-07-01T23:59:59.000Z

69

Duct thermal performance models for large commercial buildings  

SciTech Connect

Despite the potential for significant energy savings by reducing duct leakage or other thermal losses from duct systems in large commercial buildings, California Title 24 has no provisions to credit energy-efficient duct systems in these buildings. A substantial reason is the lack of readily available simulation tools to demonstrate the energy-saving benefits associated with efficient duct systems in large commercial buildings. The overall goal of the Efficient Distribution Systems (EDS) project within the PIER High Performance Commercial Building Systems Program is to bridge the gaps in current duct thermal performance modeling capabilities, and to expand our understanding of duct thermal performance in California large commercial buildings. As steps toward this goal, our strategy in the EDS project involves two parts: (1) developing a whole-building energy simulation approach for analyzing duct thermal performance in large commercial buildings, and (2) using the tool to identify the energy impacts of duct leakage in California large commercial buildings, in support of future recommendations to address duct performance in the Title 24 Energy Efficiency Standards for Nonresidential Buildings. The specific technical objectives for the EDS project were to: (1) Identify a near-term whole-building energy simulation approach that can be used in the impacts analysis task of this project (see Objective 3), with little or no modification. A secondary objective is to recommend how to proceed with long-term development of an improved compliance tool for Title 24 that addresses duct thermal performance. (2) Develop an Alternative Calculation Method (ACM) change proposal to include a new metric for thermal distribution system efficiency in the reporting requirements for the 2005 Title 24 Standards. The metric will facilitate future comparisons of different system types using a common ''yardstick''. (3) Using the selected near-term simulation approach, assess the impacts of duct system improvements in California large commercial buildings, over a range of building vintages and climates. This assessment will provide a solid foundation for future efforts that address the energy efficiency of large commercial duct systems in Title 24. This report describes our work to address Objective 1, which includes a review of past modeling efforts related to duct thermal performance, and recommends near- and long-term modeling approaches for analyzing duct thermal performance in large commercial buildings.

Wray, Craig P.

2003-10-01T23:59:59.000Z

70

Thermal modeling of the lithium/polymer battery  

DOE Green Energy (OSTI)

Research in the area of advanced batteries for electric-vehicle applications has increased steadily since the 1990 zero-emission-vehicle mandate of the California Air Resources Board. Due to their design flexibility and potentially high energy and power densities, lithium/polymer batteries are an emerging technology for electric-vehicle applications. Thermal modeling of lithium/polymer batteries is particularly important because the transport properties of the system depend exponentially on temperature. Two models have been presented for assessment of the thermal behavior of lithium/polymer batteries. The one-cell model predicts the cell potential, the concentration profiles, and the heat-generation rate during discharge. The cell-stack model predicts temperature profiles and heat transfer limitations of the battery. Due to the variation of ionic conductivity and salt diffusion coefficient with temperature, the performance of the lithium/polymer battery is greatly affected by temperature. Because of this variation, it is important to optimize the cell operating temperature and design a thermal management system for the battery. Since the thermal conductivity of the polymer electrolyte is very low, heat is not easily conducted in the direction perpendicular to cell layers. Temperature profiles in the cells are not as significant as expected because heat-generation rates in warmer areas of the cell stack are lower than heat-generation rates in cooler areas of the stack. This nonuniform heat-generation rate flattens the temperature profile. Temperature profiles as calculated by this model are not as steep as those calculated by previous models that assume a uniform heat-generation rate.

Pals, C.R. [Univ. of California, Berkeley, CA (United States). Dept. of Chemical Engineering]|[Lawrence Berkeley Lab., CA (United States). Energy and Environment Div.

1994-10-01T23:59:59.000Z

71

Introducing hysteresis in snow depletion curves to improve the water budget of a land surface model in an Alpine catchment  

Science Conference Proceedings (OSTI)

The Durance watershed (14 000 km2), located in the French Alps, generates 10% of French hydro-power and provides drinking water to 3 million people. The Catchment Land Surface Model (CLSM), a distributed land surface model (LSM) with a multilayer, ...

Claire Magand; Agnès Ducharne; Nicolas Le Moine; Simon Gascoin

72

Thermal Faults Modeling using a RC model with an Application to Web Farms  

E-Print Network (OSTI)

Today’s CPUs consume a significant amount of power and generate a high amount of heat, requiring an active cooling system to support reliable operations. In case of cooling system failures, these CPUs can reduce clock speed to prevent damage due to overheating. Unfortunately, when these CPUs are used in a real-time system, a clock control based on frequency-throttling can cause missed deadlines. In this paper, we first develop and validate a system-wide thermal model that can account for various thermal fault types such as failure of a CPU fan, faults in the case fan and air-conditioning malfunctions. Then we validate the thermal model through experimentation and measurements in AMD Linux boxes. Our soft real-time power-aware load-distribution algorithm for data centers incorporates a thermal model to minimize the number of missed deadlines that can be caused by thermal faults. We implemented the algorithm in a webserver farm simulator to test the efficacy of thermal-aware load-balancing. Our results show that the new algorithm helps keep CPU temperatures within the desired thermal envelope, even in the presence of thermal faults. When thermal faults occur, our algorithm improves the QoS, at the expense of higher energy consumption. 1

Re P. Ferreira; Daniel Mossé

2007-01-01T23:59:59.000Z

73

Influence Of Three Dynamic Predictive Clothing Insulation Models On Building Energy Use, HVAC Sizing And Thermal Comfort  

E-Print Network (OSTI)

Weather, Clothing and Thermal Adaptation to Indoor Climate,of Determining Acceptable Thermal Conditions, Building andan Adaptive Model of Thermal Comfort and Preference, Final

Schiavon, Stefano; Lee, Kwang Ho

2013-01-01T23:59:59.000Z

74

Trends in Southern Hemisphere Circulation in IPCC AR4 Models over 1950–99: Ozone Depletion versus Greenhouse Forcing  

Science Conference Proceedings (OSTI)

Simulations by the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report (AR4) models on the Southern Hemisphere (SH) circulation are assessed over the period 1950–99, focusing on the seasonality of the trend and the level of ...

Wenju Cai; Tim Cowan

2007-02-01T23:59:59.000Z

75

Modeling of thermal plasma arc technology FY 1994 report  

Science Conference Proceedings (OSTI)

The thermal plasma arc process is under consideration to thermally treat hazardous and radioactive waste. A computer model for the thermal plasma arc technology was designed as a tool to aid in the development and use of the plasma arc-Joule beating process. The value of this computer model is to: (a) aid in understanding the plasma arc-Joule beating process as applied to buried waste or exhumed buried waste, (b) help design melter geometry and electrode configuration, (c) calculate the process capability of vitrifying waste (i.e., tons/hour), (d) develop efficient plasma and melter operating conditions to optimize the process and/or reduce safety hazards, (e) calculate chemical reactions during treatment of waste to track chemical composition of off-gas products, and composition of final vitrified waste form and (f) help compare the designs of different plasma-arc facilities. A steady-state model of a two-dimensional axisymmetric transferred plasma arc has been developed and validated. A parametric analysis was performed that studied the effects of arc length, plasma gas composition, and input power on the temperatures and velocity profiles of the slag and plasma gas. A two-dimensional transient thermo-fluid model of the US Bureau of Mines plasma arc melter has been developed. This model includes the growth of a slag pool. The thermo-fluid model is used to predict the temperature and pressure fields within a plasma arc furnace. An analysis was performed to determine the effects of a molten metal pool on the temperature, velocity, and voltage fields within the slag. A robust and accurate model for the chemical equilibrium calculations has been selected to determine chemical composition of final waste form and off-gas based on the temperatures and pressures within the plasma-arc furnace. A chemical database has been selected. The database is based on the materials to be processed in the plasma arc furnaces.

Hawkes, G.L.; Nguyen, H.D.; Paik, S.; McKellar, M.G.

1995-03-01T23:59:59.000Z

76

Numerical study of error propagation in Monte Carlo depletion simulations.  

E-Print Network (OSTI)

??Improving computer technology and the desire to more accurately model the heterogeneity of the nuclear reactor environment have made the use of Monte Carlo depletion… (more)

Wyant, Timothy Joseph

2012-01-01T23:59:59.000Z

77

Thermal radiant exitance model performance: Soils and forests  

DOE Green Energy (OSTI)

Models of surface temperatures of two land surface types based on their energy budgets were developed to simulate the effects of environmental factors on thermal radiant exitance. The performance of these models is examined in detail. One model solves the non-linear differential equation for heat diffusion in solids using a set of submodels for surface energy budget components. The model performance is examined under three desert conditions thought to be a strong test of the submodels. The accuracy of the temperature predictions and submodels is described. The accuracy of the model is generally good but some discrepancies between some of the submodels and measurements are noted. The sensitivity of the submodels is examined and is seen to be strongly controlled by interaction and feedback among energy components that are a function of surface temperature. The second model simulates vegetation canopies with detailed effects of surface geometry on radiant transfer in the canopy. Foliage solar absorption coefficients are calculated using a radiosity approach for a three layer canopy and long wave fluxes are modeled using a view factor matrix. Sensible and latent heat transfer through the canopy are also simulated using, nearby meteorological data but heat storage in the canopy is not included. Simulations for a coniferous forest canopy are presented and the sensitivity of the model to environmental inputs is discussed.

Balick, L.K. [EG& G Energy Measurements Inc., Las Vegas, NV (United States); Smith, J.A. [NASA/Goddard Space Flight Center, Greenbelt, MD (United States). Lab. for Terrestrial Physics

1995-12-31T23:59:59.000Z

78

FFT-LB modeling of thermal liquid-vapor systems  

E-Print Network (OSTI)

We further develop a thermal LB model for multiphase flows. In the improved model, we propose to use the FFT scheme to calculate both the convection term and external force term. The usage of FFT scheme is detailed and analyzed. By using the FFT algorithm spatiotemporal discretization errors are decreased dramatically and the conservation of total energy is much better preserved. A direct consequence of the improvement is that the unphysical spurious velocities at the interfacial regions can be damped to neglectable scale. Together with the better conservation of total energy, the more accurate flow velocities lead to the more accurate temperature field which determines the dynamical and final states of the system. With the new model, the phase diagram of the liquid-vapor system obtained from simulation is more consistent with that from theoretical calculation. Very sharp interfaces can be achieved. The accuracy of simulation results are also verified by the Laplace law. The FFT scheme can be easily applied t...

Gan, Yanbiao; Zhang, Guangcai; Li, Yingjun

2012-01-01T23:59:59.000Z

79

Coupled Electromagnetic and Thermal Modeling of Microwave Tissue Processing  

E-Print Network (OSTI)

This study deals with 3D finite element modeling of microwave tissue processing using Comsol software 4.0. Maxwell’s equations are coupled with heat conduction equation to determine electromagnetic field distribution and temperature profile within tissue sample in a reagent inside a domestic microwave oven. The microwave power generation term is calculated. Also, temperature distribution obtained is compared with experimental point measurements recorded in the centre of the tissue using a shielded K type thermocouple. Good agreement is found between numerical and experimental data. The effect of size of both reagent and tissue as well as tissue type on microwave heating patterns within tissue sample is investigated. Studies shows that the reagent volume has greater effect than other factors. The results of the study is considered as a basic foundation for development of coupled electromagnetic thermal models of microwave heating of tissue specimens. The model assists in choosing appropriate process parameters for achieving uniform temperature distribution within tissue specimen.

Osama A Hassan; Ahmed H K; Il Ences; Ahmed M El Bialy

2013-01-01T23:59:59.000Z

80

Relative Contribution of Greenhouse Gases and Ozone-Depleting Substances to Temperature Trends in the Stratosphere: A Chemistry–Climate Model Study  

Science Conference Proceedings (OSTI)

The temperature of the stratosphere has decreased over the past several decades. Two causes contribute to that decrease: well-mixed greenhouse gases (GHGs) and ozone-depleting substances (ODSs). This paper addresses the attribution of temperature ...

Richard S. Stolarski; Anne R. Douglass; Paul A. Newman; Steven Pawson; Mark R. Schoeberl

2010-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "thermal depletion model" 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

Electrochemical-thermal modeling and microscale phase change for passive internal thermal management of lithium ion batteries.  

SciTech Connect

A fully coupled electrochemical and thermal model for lithium-ion batteries is developed to investigate the impact of different thermal management strategies on battery performance. In contrast to previous modeling efforts focused either exclusively on particle electrochemistry on the one hand or overall vehicle simulations on the other, the present work predicts local electrochemical reaction rates using temperature-dependent data on commercially available batteries designed for high rates (C/LiFePO{sub 4}) in a computationally efficient manner. Simulation results show that conventional external cooling systems for these batteries, which have a low composite thermal conductivity ({approx}1 W/m-K), cause either large temperature rises or internal temperature gradients. Thus, a novel, passive internal cooling system that uses heat removal through liquid-vapor phase change is developed. Although there have been prior investigations of phase change at the microscales, fluid flow at the conditions expected here is not well understood. A first-principles based cooling system performance model is developed and validated experimentally, and is integrated into the coupled electrochemical-thermal model for assessment of performance improvement relative to conventional thermal management strategies. The proposed cooling system passively removes heat almost isothermally with negligible thermal resistances between the heat source and cooling fluid. Thus, the minimization of peak temperatures and gradients within batteries allow increased power and energy densities unencumbered by thermal limitations.

Fuller, Thomas F. (Georgia Institute of Technology, Atlanta, GA); Bandhauer, Todd (Georgia Institute of Technology, Atlanta, GA); Garimella, Srinivas (Georgia Institute of Technology, Atlanta, GA)

2012-01-01T23:59:59.000Z

82

Thermal/Electrical Modeling for Abuse-Tolerant Design of Li-Ion Modules (Presentation)  

DOE Green Energy (OSTI)

To help design safe, high-performing batteries, NREL and NASA created and verified a new multicell math model capturing electrical-thermal interactions of cells with PTC devices during thermal abuse.

Smith, K.; Kim, G.-H.; Pesaran, A.; Darcy, E.

2008-11-01T23:59:59.000Z

83

Energy Storage R&D: Thermal Management Studies and Modeling (Presentation)  

DOE Green Energy (OSTI)

Here we summarize NREL's FY09 energy storage R&D studies in the areas of 1. thermal characterization and analysis, 2. cost, life, and performance trade-off studies, and 3. thermal abuse modeling.

Pesaran, A. A.

2009-05-01T23:59:59.000Z

84

A Cumulus Parameterization Based on a Cloud Model of Intermittently Rising Thermals  

Science Conference Proceedings (OSTI)

The author presents a cumulus parameterization that uses a cloud model that describes atmospheric convection as consisting of a sequence of intermittently rising thermals. The total mass of thermals in a convection event is determined by the ...

Qi Hu

1997-09-01T23:59:59.000Z

85

Energy Storage R&D: Thermal Management Studies and Modeling (Presentation)  

SciTech Connect

Here we summarize NREL's FY09 energy storage R&D studies in the areas of 1. thermal characterization and analysis, 2. cost, life, and performance trade-off studies, and 3. thermal abuse modeling.

Pesaran, A. A.

2009-05-01T23:59:59.000Z

86

Depleted uranium management alternatives  

SciTech Connect

This report evaluates two management alternatives for Department of Energy depleted uranium: continued storage as uranium hexafluoride, and conversion to uranium metal and fabrication to shielding for spent nuclear fuel containers. The results will be used to compare the costs with other alternatives, such as disposal. Cost estimates for the continued storage alternative are based on a life-cycle of 27 years through the year 2020. Cost estimates for the recycle alternative are based on existing conversion process costs and Capital costs for fabricating the containers. Additionally, the recycle alternative accounts for costs associated with intermediate product resale and secondary waste disposal for materials generated during the conversion process.

Hertzler, T.J.; Nishimoto, D.D.

1994-08-01T23:59:59.000Z

87

Video: The Depleted Uranium Hexafluoride Story  

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

Depleted UF6 Story The Depleted Uranium Hexafluoride Story An overview of Uranium, its isotopes, the need and history of diffusive separation, the handling of the Depleted Uranium...

88

Acceptability of Four Transformer Top-Oil Thermal Models: Pt. 2: Comparing Metrics  

E-Print Network (OSTI)

1 Acceptability of Four Transformer Top-Oil Thermal Models: Pt. 2: Comparing Metrics Lida Jauregui transformer top-oil thermal models are examined vis-à-vis training with measured data. Acceptability is unacceptable for model identification purposes. The linear top-oil model is acceptable for FOFA transformers

89

Abstract--Eventually, prediction of transformer thermal performance for dynamic loading will be made using models  

E-Print Network (OSTI)

1 Abstract--Eventually, prediction of transformer thermal performance for dynamic loading will be made using models distilled from measure data, rather than models derived from transformer heat for measuring the acceptability of transformer thermal models. For a model to be acceptable, it must have

90

Polyethylene Encapsulated Depleted Uranium  

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

Poly DU Poly DU Polyethylene Encapsulated Depleted Uranium Technology Description: Brookhaven National Laboratory (BNL) has completed preliminary work to investigate the feasibility of encapsulating DU in low density polyethylene to form a stable, dense product. DU loadings as high as 90 wt% were achieved. A maximum product density of 4.2 g/cm3 was achieved using UO3, but increased product density using UO2 is estimated at 6.1 g/cm3. Additional product density improvements up to about 7.2 g/cm3 were projected using DU aggregate in a hybrid technique known as micro/macroencapsulation.[1] A U.S. patent for this process has been received.[2] Figure 1 Figure 1: DU Encapsulated in polyethylene samples produced at BNL containing 80 wt % depleted UO3 A recent DU market study by Kapline Enterprises, Inc. for DOE thoroughly identified and rated potential applications and markets for DU metal and oxide materials.[3] Because of its workability and high DU loading capability, the polyethylene encapsulated DU could readily be fabricated as counterweights/ballast (for use in airplanes, helicopters, ships and missiles), flywheels, armor, and projectiles. Also, polyethylene encapsulated DU is an effective shielding material for both gamma and neutron radiation, with potential application for shielding high activity waste (e.g., ion exchange resins, glass gems), spent fuel dry storage casks, and high energy experimental facilities (e.g., accelerator targets) to reduce radiation exposures to workers and the public.

91

FFT-LB modeling of thermal liquid-vapor systems  

E-Print Network (OSTI)

We further develop a thermal LB model for multiphase flows. In the improved model, we propose to use the FFT scheme to calculate both the convection term and external force term. The usage of FFT scheme is detailed and analyzed. By using the FFT algorithm spatiotemporal discretization errors are decreased dramatically and the conservation of total energy is much better preserved. A direct consequence of the improvement is that the unphysical spurious velocities at the interfacial regions can be damped to neglectable scale. Together with the better conservation of total energy, the more accurate flow velocities lead to the more accurate temperature field which determines the dynamical and final states of the system. With the new model, the phase diagram of the liquid-vapor system obtained from simulation is more consistent with that from theoretical calculation. Very sharp interfaces can be achieved. The accuracy of simulation results are also verified by the Laplace law. The FFT scheme can be easily applied to other models for multiphase flows.

Yanbiao Gan; Aiguo Xu; Guangcai Zhang; Yingjun Li

2010-11-16T23:59:59.000Z

92

Coupled Thermal-Chemical-Mechanical Modeling of Validation Cookoff Experiments  

DOE Green Energy (OSTI)

The cookoff of energetic materials involves the combined effects of several physical and chemical processes. These processes include heat transfer, chemical decomposition, and mechanical response. The interaction and coupling between these processes influence both the time-to-event and the violence of reaction. The prediction of the behavior of explosives during cookoff, particularly with respect to reaction violence, is a challenging task. To this end, a joint DoD/DOE program has been initiated to develop models for cookoff, and to perform experiments to validate those models. In this paper, a series of cookoff analyses are presented and compared with data from a number of experiments for the aluminized, RDX-based, Navy explosive PBXN-109. The traditional thermal-chemical analysis is used to calculate time-to-event and characterize the heat transfer and boundary conditions. A reaction mechanism based on Tarver and McGuire's work on RDX{sup 2} was adjusted to match the spherical one-dimensional time-to-explosion data. The predicted time-to-event using this reaction mechanism compares favorably with the validation tests. Coupled thermal-chemical-mechanical analysis is used to calculate the mechanical response of the confinement and the energetic material state prior to ignition. The predicted state of the material includes the temperature, stress-field, porosity, and extent of reaction. There is little experimental data for comparison to these calculations. The hoop strain in the confining steel tube gives an estimation of the radial stress in the explosive. The inferred pressure from the measured hoop strain and calculated radial stress agree qualitatively. However, validation of the mechanical response model and the chemical reaction mechanism requires more data. A post-ignition burn dynamics model was applied to calculate the confinement dynamics. The burn dynamics calculations suffer from a lack of characterization of the confinement for the flaw-dominated failure mode experienced in the tests. High-pressure burning rates are needed for more detailed post-ignition studies. Sub-models for chemistry, mechanical response and burn dynamics need to be validated against data from less complex experiments. The sub-models can then be used in integrated analysis for comparison with experimental data taken during integrated tests.

ERIKSON,WILLIAM W.; SCHMITT,ROBERT G.; ATWOOD,A.I.; CURRAN,P.D.

2000-11-27T23:59:59.000Z

93

Development and evaluation of a thermal model for haptic interfaces  

E-Print Network (OSTI)

The thermal interaction between the skin and an object is influenced by the thermal properties and initial temperatures of the skin and object, and by the contact force and surface roughness of the contact surfaces. This ...

Ho, Hsin-Ni

2007-01-01T23:59:59.000Z

94

Influence of the temperature dependence of thermal parameters of heat conduction models on the reconstruction of thermal history of igneous-intrusion-bearing basins  

Science Conference Proceedings (OSTI)

Heat conduction models are important tools for reconstructing the thermal history of sedimentary basins affected by magmatic intrusions. Accurate thermal properties of the intrusion and its wall rocks are crucial for accurate predictions of thermal history. ... Keywords: Igneous intrusion, Peak temperature, Specific heat, Thermal conductivity, Vitrinite reflectance

Dayong Wang; Xiancai Lu; Yongchen Song; Rong Shao; Tian Qi

2010-10-01T23:59:59.000Z

95

A model for the shallow thermal regime at Dixie Valley geothermal field |  

Open Energy Info (EERE)

A model for the shallow thermal regime at Dixie Valley geothermal field A model for the shallow thermal regime at Dixie Valley geothermal field Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article: A model for the shallow thermal regime at Dixie Valley geothermal field Authors R. G. Allis, Stuart D. Johnson, Gregory D. Nash and Dick Benoit Published Journal TRANSACTIONS-GEOTHERMAL RESOURCES COUNCIL, 1999 DOI Not Provided Check for DOI availability: http://crossref.org Online Internet link for A model for the shallow thermal regime at Dixie Valley geothermal field Citation R. G. Allis,Stuart D. Johnson,Gregory D. Nash,Dick Benoit. 1999. A model for the shallow thermal regime at Dixie Valley geothermal field. TRANSACTIONS-GEOTHERMAL RESOURCES COUNCIL. 23:493-498. Retrieved from "http://en.openei.org/w/index.php?title=A_model_for_the_shallow_thermal_regime_at_Dixie_Valley_geothermal_field&oldid=682587"

96

Power distributions in fresh and depleted LEU and HEU cores of the MITR reactor.  

Science Conference Proceedings (OSTI)

The Massachusetts Institute of Technology Reactor (MITR-II) is a research reactor in Cambridge, Massachusetts designed primarily for experiments using neutron beam and in-core irradiation facilities. It delivers a neutron flux comparable to current LWR power reactors in a compact 6 MW core using Highly Enriched Uranium (HEU) fuel. In the framework of its non-proliferation policies, the international community presently aims to minimize the amount of nuclear material available that could be used for nuclear weapons. In this geopolitical context, most research and test reactors both domestic and international have started a program of conversion to the use of Low Enriched Uranium (LEU) fuel. A new type of LEU fuel based on an alloy of uranium and molybdenum (UMo) is expected to allow the conversion of U.S. domestic high performance reactors like the MITR-II reactor. Toward this goal, core geometry and power distributions are presented. Distributions of power are calculated for LEU cores depleted with MCODE using an MCNP5 Monte Carlo model. The MCNP5 HEU and LEU MITR models were previously compared to experimental benchmark data for the MITR-II. This same model was used with a finer spatial depletion in order to generate power distributions for the LEU cores. The objective of this work is to generate and characterize a series of fresh and depleted core peak power distributions, and provide a thermal hydraulic evaluation of the geometry which should be considered for subsequent thermal hydraulic safety analyses.

Wilson, E.H.; Horelik, N.E.; Dunn, F.E.; Newton, T.H., Jr.; Hu, L.; Stevens, J.G. (Nuclear Engineering Division); (2MIT Nuclear Reactor Laboratory and Nuclear Science and Engineering Department)

2012-04-04T23:59:59.000Z

97

Mathematical models of thermal and chemical transport in geologic media  

DOE Green Energy (OSTI)

Semi-analytical and numerical methods are used to investigate thermal and chemical transport processes in geologic media. The work is divided into two parts: (1) development of semi-analytical models for the analysis of uncoupled isothermal and nonisothermal fluid flow in naturally fractured media, and (2) development of a high resolution numerical code to address coupled nonisothermal chemical transport in geologic media. A semi-analytical model is developed for well test data analysis in naturally fractured reservoirs. A simple approximate analytical solution for pressure buildup and drawdown tests is developed. Methods based on the approximate solution are developed for the evaluation of important reservoir properties. Type curves for nonisothermal fluid flow in naturally fractured media are developed to design injection systems for maximum energy in hydrothermal systems. An accurate finite difference method for the solution of a convection-diffusion type equation is developed. The method is incorporated in a two-dimensional code to investigate free convection in a porous slab and kinetic silica-water reactions in geothermal systems. A multicomponent model considering the variations of pressure, temperature and silica concentration is developed to interpret the evolution of geothermal systems during exploitation.

Lai, C.-H.

1985-12-01T23:59:59.000Z

98

Design Considerations, Modeling and Analysis for the Multispectral Thermal Imager  

SciTech Connect

The design of remote sensing systems is driven by the need to provide cost-effective, substantive answers to questions posed by our customers. This is especially important for space-based systems, which tend to be expensive, and which generally cannot be changed after they are launched. We report here on the approach we employed in developing the desired attributes of a satellite mission, namely the Multispectral Thermal Imager. After an initial scoping study, we applied a procedure which we call: "End-to-end modeling and analysis (EEM)." We began with target attributes, translated to observable signatures and then propagated the signatures through the atmosphere to the sensor location. We modeled the sensor attributes to yield a simulated data stream, which was then analyzed to retrieve information about the original target. The retrieved signature was then compared to the original to obtain a figure of merit: hence the term "end-to-end modeling and analysis." We base the EEM in physics to ensure high fidelity and to permit scaling. As the actual design of the payload evolves, and as real hardware is tested, we can update the EEM to facilitate trade studies, and to judge, for example, whether components that deviate from specifications are acceptable.

Borel, C.C.; Clodius, W.B.; Cooke, B.J.; Smith, B.W.; Weber, P.G.

1999-02-01T23:59:59.000Z

99

Modelling the vertical heat exchanger in thermal basin  

Science Conference Proceedings (OSTI)

In geographical area characterize by specific geological conformations such as the Viterbo area which comprehend active volcanic basins, it is difficult to use conventional geothermal plants. In fact the area presents at shallow depths thermal falde ... Keywords: heat, thermal aquifer, thermal energy

Maurizio Carlini; Sonia Castellucci

2007-06-01T23:59:59.000Z

100

Depleted Uranium Hexafluoride Management  

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

for for DUF 6 Conversion Project Environmental Impact Statement Scoping Meetings November/December 2001 Overview Depleted Uranium Hexafluoride (DUF 6 ) Management Program DUF 6 EIS Scoping Briefing 2 DUF 6 Management Program Organizational Chart DUF 6 Management Program Organizational Chart EM-10 Policy EM-40 Project Completion EM-20 Integration EM-50 Science and Technology EM-31 Ohio DUF6 Management Program EM-32 Oak Ridge EM-33 Rocky Flats EM-34 Small Sites EM-30 Office of Site Closure Office of Environmental Management EM-1 DUF 6 EIS Scoping Briefing 3 DUF 6 Management Program DUF 6 Management Program * Mission: Safely and efficiently manage the DOE inventory of DUF 6 in a way that protects the health and safety of workers and the public, and protects the environment DUF 6 EIS Scoping Briefing 4 DUF 6 Inventory Distribution

Note: This page contains sample records for the topic "thermal depletion model" 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

Dynamic thermal modelling of a power integrated circuit with the application of structure functions  

Science Conference Proceedings (OSTI)

This paper presents dynamic thermal analyses of a power integrated circuit with a cooling assembly. The investigations are based on the examination of the cumulative and differential structure functions obtained from the circuit cooling curves recorded ... Keywords: Contact thermal resistance, Heat transfer coefficient, Structure function, Thermal modelling and simulation

Marcin Janicki; Jedrzej Banaszczyk; Gilbert De Mey; Marek Kaminski; Bjorn Vermeersch; Andrzej Napieralski

2009-07-01T23:59:59.000Z

102

Numerical modeling of self-limiting and self-enhancing caprock alteration induced by CO2 storage in a depleted gas reservoir  

Science Conference Proceedings (OSTI)

This paper presents numerical simulations of reactive transport which may be induced in the caprock of an on-shore depleted gas reservoir by the geological sequestration of carbon dioxide. The objective is to verify that CO{sub 2} geological disposal activities currently being planned for the study area are safe and do not induce any undesired environmental impact. In our model, fluid flow and mineral alteration are induced in the caprock by penetration of high CO{sub 2} concentrations from the underlying reservoir, where it was assumed that large amounts of CO{sub 2} have already been injected at depth. The main focus is on the potential effect of precipitation and dissolution processes on the sealing efficiency of caprock formations. Concerns that some leakage may occur in the investigated system arise because the seal is made up of potentially highly-reactive rocks, consisting of carbonate-rich shales (calcite+dolomite averaging up to more than 30% of solid volume fraction). Batch simulations and multi-dimensional 1D and 2D modeling have been used to investigate multicomponent geochemical processes. Numerical simulations account for fracture-matrix interactions, gas phase participation in multiphase fluid flow and geochemical reactions, and kinetics of fluid-rock interactions. The geochemical processes and parameters to which the occurrence of high CO{sub 2} concentrations are most sensitive are investigated by conceptualizing different mass transport mechanisms (i.e. diffusion and mixed advection+diffusion). The most relevant mineralogical transformations occurring in the caprock are described, and the feedback of these geochemical processes on physical properties such as porosity is examined to evaluate how the sealing capacity of the caprock could evolve in time. The simulations demonstrate that the occurrence of some gas leakage from the reservoir may have a strong influence on the geochemical evolution of the caprock. In fact, when a free CO{sub 2}-dominated phase migrates into the caprock through fractures, or through zones with high initial porosity possibly acting as preferential flow paths for reservoir fluids, low pH values are predicted, accompanied by significant calcite dissolution and porosity enhancement. In contrast, when fluid-rock interactions occur under fully liquid-saturated conditions and a diffusion-controlled regime, pH will be buffered at higher values, and some calcite precipitation is predicted which leads to further sealing of the storage reservoir.

Xu, Tianfu; Gherardi, Fabrizio; Xu, Tianfu; Pruess, Karsten

2007-09-07T23:59:59.000Z

103

Matchstick: a room-to-room thermal model for predicting indoor temperature from wireless sensor data  

Science Conference Proceedings (OSTI)

In this paper we present a room-to-room thermal model used to accurately predict temperatures in residential buildings. We evaluate the accuracy of this model with ground truth data from four occupied family homes (two in the UK and two in the US). The ... Keywords: forced air, home automation, prediction, radiators, thermal modelling, underfloor heating

Carl Ellis; Mike Hazas; James Scott

2013-04-01T23:59:59.000Z

104

Matchstick: A Room-to-Room Thermal Model for Predicting Indoor Temperature from Wireless Sensor Data  

E-Print Network (OSTI)

Matchstick: A Room-to-Room Thermal Model for Predicting Indoor Temperature from Wireless Sensor present a room-to-room thermal model used to accurately predict temperatures in residential buildings. We that our model can predict future indoor temperature trends with a 90th percentile aggregate error between

Hazas, Mike

105

The New MCNP6 Depletion Capability  

SciTech Connect

The first MCNP based inline Monte Carlo depletion capability was officially released from the Radiation Safety Information and Computational Center as MCNPX 2.6.0. Both the MCNP5 and MCNPX codes have historically provided a successful combinatorial geometry based, continuous energy, Monte Carlo radiation transport solution for advanced reactor modeling and simulation. However, due to separate development pathways, useful simulation capabilities were dispersed between both codes and not unified in a single technology. MCNP6, the next evolution in the MCNP suite of codes, now combines the capability of both simulation tools, as well as providing new advanced technology, in a single radiation transport code. We describe here the new capabilities of the MCNP6 depletion code dating from the official RSICC release MCNPX 2.6.0, reported previously, to the now current state of MCNP6. NEA/OECD benchmark results are also reported. The MCNP6 depletion capability enhancements beyond MCNPX 2.6.0 reported here include: (1) new performance enhancing parallel architecture that implements both shared and distributed memory constructs; (2) enhanced memory management that maximizes calculation fidelity; and (3) improved burnup physics for better nuclide prediction. MCNP6 depletion enables complete, relatively easy-to-use depletion calculations in a single Monte Carlo code. The enhancements described here help provide a powerful capability as well as dictate a path forward for future development to improve the usefulness of the technology.

Fensin, Michael Lorne [Los Alamos National Laboratory; James, Michael R. [Los Alamos National Laboratory; Hendricks, John S. [Los Alamos National Laboratory; Goorley, John T. [Los Alamos National Laboratory

2012-06-19T23:59:59.000Z

106

Development of a Thermal Model for an Inner Stator Type Reluctance Motor.  

E-Print Network (OSTI)

??Thermal modeling is an important aspect of electric motor design. Numerous techniques exist to predict the temperatures in a motor, and they can be incorporated… (more)

Pieterse, Michael

2009-01-01T23:59:59.000Z

107

Depleted UF6 Overview Presentation  

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

Information network Web Site. The presentation covers the following topics: The uranium mining and enrichment processes - how depleted UF6 is created, How and where...

108

Particle Production at CBM in a Thermal Model Approach  

E-Print Network (OSTI)

The Compressed Baryonic Matter (CBM) experiment planned at Facility for Antiproton and Ion Research (FAIR) will provide a major scientific effort for exploring the properties of strongly interacting matter in the high baryon density regime. One of the important goal behind such experiment is to precisely determine the equation of state (EOS) for the strongly interacting matter at extreme baryon density. In this paper, we have used a thermal model EOS incorporating excluded volume description for the hot and dense hadron gas (HG). We then predict different particle ratios and the total multiplicity of various hadrons in the CBM energy range i.e. from $10$ A GeV to $40$ A GeV lab energies, which corresponds to $4.43$ A GeV and $8.71$ A GeV center-of-mass energies. Our main emphasis is to estimate the strange particles enhancement as well as increase in the net baryon density in CBM experiment. We have also compared our results with the results obtained from various other theoretical approaches existing in the literature such as hadron string dynamics (HSD) model and ultra-relativistic quantum molecular dynamics (UrQMD) etc.

A. Prakash; P. K. Srivastava; B. K. Singh

2013-08-19T23:59:59.000Z

109

Modeling of thermal transport properties of multiphase porous materials  

Science Conference Proceedings (OSTI)

This work presents a numerical framework for modeling thermal transport properties of multiphase porous materials with complex internal microstructures. The framework includes two steps. First, a random generation-growth algorithm is highlighted for reproducing multiphase microstructures, statistically equivalent to the actual systems, based on the geometrical and morphological information obtained from measurements and experimental estimations. Then a high-efficiency lattice Boltzmann solver for the corresponding governing equations is described, which, while assuring energy conservation and appropriate continuities at the interfaces in a complex system, has demonstrated its numerical power in yielding accurate solutions. Various applications are provided to validate the feasibility, effectiveness and robustness of this new framework by comparing the predictions with existing experimental data for different transport processes, accounting for the effects due to internal morphology, microstructural anisotropy, and multi phase interactions. The examples given also suggest potential applicability of this methodology to other problems as long as they are governed by similar partial differential equation(s). Thus, for given composition and structure, this numerical methodology is in essence a model built on sound physics principles with prior validity, without resorting to any ad hoc empirical treatment. Therefore, it is useful for design and optimization of new materials, beyond just predicting and analyzing the existing ones.

Wang, Moran [Los Alamos National Laboratory; Kang, Qinjun [Los Alamos National Laboratory; Robinson, Bruce [Los Alamos National Laboratory; Ning, Pan [UC DAVIS

2010-01-01T23:59:59.000Z

110

Rapid Modeling of Power Electronics Thermal Management Technologies: Preprint  

DOE Green Energy (OSTI)

Describes a method of rapidly evaluating trade-offs associated with alternative packaging configurations and thermal management technologies for power electronics packaging.

Bennion, K.; Kelly, K.

2009-08-01T23:59:59.000Z

111

A Geothermal Field Model Based On Geophysical And Thermal Prospectings...  

Open Energy Info (EERE)

results of some deep electrical soundings (AB 6000 m) with the interpretation of a gravity profile crossing the investigated area are considered together with thermal...

112

Evaluation of the gas production economics of the gas hydrate cyclic thermal injection model. [Cyclic thermal injection  

SciTech Connect

The objective of the work performed under this directive is to assess whether gas hydrates could potentially be technically and economically recoverable. The technical potential and economics of recovering gas from a representative hydrate reservoir will be established using the cyclic thermal injection model, HYDMOD, appropriately modified for this effort, integrated with economics model for gas production on the North Slope of Alaska, and in the deep offshore Atlantic. The results from this effort are presented in this document. In Section 1, the engineering cost and financial analysis model used in performing the economic analysis of gas production from hydrates -- the Hydrates Gas Economics Model (HGEM) -- is described. Section 2 contains a users guide for HGEM. In Section 3, a preliminary economic assessment of the gas production economics of the gas hydrate cyclic thermal injection model is presented. Section 4 contains a summary critique of existing hydrate gas recovery models. Finally, Section 5 summarizes the model modification made to HYDMOD, the cyclic thermal injection model for hydrate gas recovery, in order to perform this analysis.

Kuuskraa, V.A.; Hammersheimb, E.; Sawyer, W.

1985-05-01T23:59:59.000Z

113

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

E-Print Network (OSTI)

Tsang, Y.W. : Modeling the thermal-hydrologic processes in aanalyses of heterogeneity and thermal-loading factors for a2005 Lin, W. , Sun, Y. : Thermal hydrological processes in

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

2010-01-01T23:59:59.000Z

114

Novel Charging Station and Computational Modeling for High Thermal Conductivity Heat Pipe Thermal Ground Planes.  

E-Print Network (OSTI)

??Thermal ground planes (TGPs) are planar, thin (thickness of 3 mm or less) heat pipes which use two-phase heat transfer. TGPs are innovative high-performance, integrated… (more)

Ababneh, Mohammed

2012-01-01T23:59:59.000Z

115

THERMAL MODELING ANALYSIS OF SRS 70 TON CASK  

SciTech Connect

The primary objective of this work was to perform the thermal calculations to evaluate the Material Test Reactor (MTR) fuel assembly temperatures inside the SRS 70-Ton Cask loaded with various bundle powers. MTR fuel consists of HFBR, MURR, MIT, and NIST. The MURR fuel was used to develop a bounding case since it is the fuel with the highest heat load. The results will be provided for technical input for the SRS 70 Ton Cask Onsite Safety Assessment. The calculation results show that for the SRS 70 ton dry cask with 2750 watts total heat source with a maximum bundle heat of 670 watts and 9 bundles of MURR bounding fuel, the highest fuel assembly temperatures are below about 263 C. Maximum top surface temperature of the plastic cover is about 112 C, much lower than its melting temperature 260 C. For 12 bundles of MURR bounding fuel with 2750 watts total heat and a maximum fuel bundle of 482 watts, the highest fuel assembly temperatures are bounded by the 9 bundle case. The component temperatures of the cask were calculated by a three-dimensional computational fluid dynamics approach. The modeling calculations were performed by considering daily-averaged solar heat flux.

Lee, S.; Jordan, J.; Hensel, S.

2011-03-08T23:59:59.000Z

116

Modelling the convective flow in solar thermal receivers K.C. Yeh; G. Hughes & K. Lovegrove  

E-Print Network (OSTI)

Modelling the convective flow in solar thermal receivers K.C. Yeh; G. Hughes & K. Lovegrove density differences produced using the varying salt concentrations in a water tank. The flow to visualise #12;Modelling the Convective Flow in Solar Thermal Receivers Yeh the flow outside the cavity mouth

117

Market power and welfare effects in DC power flow electricity models with thermal line losses  

Science Conference Proceedings (OSTI)

A nodal electric power network with Cournot-Nash interaction among power generators is formulated as a mixed complementarity problem. The model incorporates a direct current (DC) power flow approximation with thermal line losses to model real-time flows. ... Keywords: Electricity markets, Imperfect competition, Thermal line losses, Welfare measurement

Rastislav Ivanic; Paul V. Preckel; Zuwei Yu

2005-10-01T23:59:59.000Z

118

Thermal Expansion in Ocean and Coupled General Circulation Models  

Science Conference Proceedings (OSTI)

More than half of the predicted rise in future sea level caused by the enhanced greenhouse effect is currently thought to be due to the thermal expansion of the oceans. Here methods for quantifying this thermal expansion component of sea level ...

D. R. Jackett; T. J. McDougall; M. H. England; A. C. Hirst

2000-04-01T23:59:59.000Z

119

Modeling and testing of a thermal transient anemometer  

SciTech Connect

The Thermal Transient Anemometer (TTA) is a fluid mass flow measuring device which utilizes a thermocouple as a probe. The probe is periodically heated by an electric current pulse through the thermocouple junction, and the measured rate of cooling between pulses is related to the local mean flow velocity. The standard thermocouple sensor provides an inexpensive flow probe which is durable, rugged, and capable of satisfactory operation in hostile environments. The TTA was developed and patented in prototype form by Instrument Development for Applied Physics (IDAP), a small US company. IDAP has tested the TTA and shown that the measurement principle is valid. However, there is a need to refine the prototype so that the TTA becomes a commercially viable instrument. The main concern is to reduce the heating current to the TTA so that battery-powered operation is possible. To do this, a probe needs to be developed such that only the region local to the thermocouple junction is heated, rather than the entire length of the wire. There area number of ways that this might be done, and IDAP has worked with ARi Industries, a thermocouple manufacturer, to develop probe designs that would have this characteristic, and at the same time would retain the ruggedness and ease of manufacture of a standard thermocouple. The purpose of this CRADA was to investigate these designs with a view to their possible commercial development. The starting point was to develop a computer model of the TTA as it currently exists, i.e., the prototype configuration, and to compare the results with experimental data. Good agreement between model and data was obtained, thus allowing new designs to be analyzed with some confidence.

Page, R.J.

1996-10-01T23:59:59.000Z

120

Gravitational Potential Energy Balance for the Thermal Circulation in a Model Ocean  

Science Conference Proceedings (OSTI)

The gravitational potential energy balance of the thermal circulation in a simple rectangular model basin is diagnosed from numerical experiments based on a mass-conserving oceanic general circulation model. The vertical mixing coefficient is ...

Rui Xin Huang; Xingze Jin

2006-07-01T23:59:59.000Z

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


121

Improving the Fanger model's thermal comfort predictions for naturally ventilated spaces  

E-Print Network (OSTI)

The Fanger model is the official thermal comfort model in U.S. and international standards and is based on the heat balance of the human body with the environment. This investigation focuses on re-specifying the parameters ...

Truong, Phan Hue

2010-01-01T23:59:59.000Z

122

Thermal Tides in the Atmosphere of Venus: Comparison of Model Results with Observations  

Science Conference Proceedings (OSTI)

A linearized primitive equation (LPE) model is developed to study thermal tides in the atmosphere of Venus. The LPE model describes diurnal and semidiurnal oscillations of a cyclostrophically balanced atmosphere in which zonal velocity varies ...

Judith Burt Pechmann; Andrew P. Ingersoll

1984-11-01T23:59:59.000Z

123

News Media Exits for Depleted Uranium and Depleted UF6 Articles  

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

line line Archived News and Events News Media Links News Media Exits for Depleted Uranium and Depleted UF6 Articles Online editions of newspapers that cover Depleted Uranium...

124

Ratings of Transmission Lines: Applications, Computations, and Thermal Models  

Science Conference Proceedings (OSTI)

The thermal rating of overhead transmission lines can be complex, because there is no way to directly measure the line rating and because high current load events occur only rarely in most parts of the power system. A thermal line rating is a prediction of how the conductor will behave thermally, mechanically, and electrically in the event of a high electrical current. It is possible to calculate ratings incorrectly and not discover that this is true until a most inopportune timeduring a system emergency...

2011-12-16T23:59:59.000Z

125

Thermal properties of nanowires and nanotubes : modeling and experiments  

E-Print Network (OSTI)

Nanowires and nanotubes have drawn a great deal of recent attention for such potential applications as lasers, transistors, biosensors, and thermoelectric energy converters. Although the thermal properties of nanowires can ...

Dames, Christopher Eric

2006-01-01T23:59:59.000Z

126

The Need for a Full-Chip and Package Thermal Model for Thermally Optimized IC Designs  

E-Print Network (OSTI)

ceramic ball-grid array (CBGA) pack- age consisting of the chip (die), thermal interface material, heat to the heat spreader. The fact that detailed package information is needed to build an accurate com- pact spreader, heat sink and other layers of packaging components is shown in Fig. 1. Through this package, heat

Skadron, Kevin

127

Depleted Uranium (DU) Dioxide Fill  

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

Fill Depleted Uranium (DU) Dioxide Fill DU dioxide in the form of sand may be used to fill the void spaces in the waste package after the package is loaded with SNF. This...

128

Depleted UF6 Health Risks  

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

(depleted UF6) is released to the atmosphere, the uranium compounds and hydrogen fluoride (HF) gas that are formed by reaction with moisture in the air can be chemically...

129

Depleted UF6 Internet Resources  

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

DUF6 Guide DU Uses DUF6 Management and Uses DUF6 Conversion EIS Documents News FAQs Internet Resources Glossary Home Internet Resources Depleted UF6 Internet Resources Links...

130

FAQ 6-What is depleted uranium?  

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

depleted uranium? What is depleted uranium? Depleted uranium is created during the processing that is done to make natural uranium suitable for use as fuel in nuclear power plants...

131

Uranio impoverito: perché? (Depleted uranium: why?)  

E-Print Network (OSTI)

In this paper we develop a simple model of the penetration process of a long rod through an uniform target. Applying the momentum and energy conservation laws, we derive an analytical relation which shows how the penetration depth depends upon the density of the rod, given a fixed kinetic energy. This work was sparked off by the necessity of understanding the effectiveness of high density penetrators (e.g. depleted uranium penetrators) as anti-tank weapons.

Germano D'Abramo

2003-05-28T23:59:59.000Z

132

A Scalable Modeling Technique to Estimate Dynamic Thermal Design Power of Datapath Intensive Designs  

Science Conference Proceedings (OSTI)

In this paper, a power modeling approach for the estimation of dynamic power under Thermal Design Power (TDP1) for datapath intensive designs is proposed. Early estimation of TDP is crucial for the design of thermal and cooling solutions of a chip and ...

Prashant Agrawal; Srinivasa R. STG; Ajit N. Oke; Saurabh Vijay

2007-03-01T23:59:59.000Z

133

A Local Model Networks Based Multivariable Long-Range Predictive Control Strategy for Thermal Power Plants  

Science Conference Proceedings (OSTI)

Load-cycling operation of thermal power plants leads to changes in operating point right across the whole operating range. This results in non-linear variations in most of the plant variables. This paper investigates methods to account for non-linearities ... Keywords: Constrained multivariable control, local model networks, long range predictive control, thermal power plant boiler

G. PRASAD; E. SWIDENBANK; B. W. HOGG

1998-10-01T23:59:59.000Z

134

Development of Detailed Kinetic Models for the Thermal Conversion of Biomass via First  

E-Print Network (OSTI)

Chapter 10 Development of Detailed Kinetic Models for the Thermal Conversion of Biomass via First. In this contribution we discuss four selected example systems related to the thermal conversion of biomass reaction steps, for the biomass gasification process would be of tremendous value to engineers who try

Dean, Anthony M.

135

Environmental Risks of Depleted UF6 Disposal  

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

Depleted UF6 Environmental Risks line line Storage Conversion Manufacturing Disposal Environmental Risks of Depleted UF6 Disposal A discussion of the environmental impacts...

136

Pennsylvania Natural Gas Underground Storage Depleted Fields...  

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

Underground Storage Depleted Fields Capacity (Million Cubic Feet) Pennsylvania Natural Gas Underground Storage Depleted Fields Capacity (Million Cubic Feet) Decade Year-0 Year-1...

137

Thermal Abuse Modeling of Li-Ion Cells and Propagation in Modules (Presentation)  

DOE Green Energy (OSTI)

The objectives of this paper are: (1) continue to explore thermal abuse behaviors of Li-ion cells and modules that are affected by local conditions of heat and materials; (2) use the 3D Li-ion battery thermal abuse 'reaction' model developed for cells to explore the impact of the location of internal short, its heating rate, and thermal properties of the cell; (3) continue to understand the mechanisms and interactions between heat transfer and chemical reactions during thermal runaway for Li-ion cells and modules; and (4) explore the use of the developed methodology to support the design of abuse-tolerant Li-ion battery systems.

Kim, G.-H.; Pesaran, A.; Smith, K.

2008-05-01T23:59:59.000Z

138

Efficient thermal field computation in phase-field models  

Science Conference Proceedings (OSTI)

We solve the phase-field equations in two dimensions to simulate crystal growth in the low undercooling regime. The novelty is the use of a fast solver for the free space heat equation to compute the thermal field. This solver is based on the efficient ... Keywords: Crystal growth, Dendritic solidification, Diffusion equation, Fast solvers, Integral representation, Phase-field, Unbounded domain

Jing-Rebecca Li; Donna Calhoun; Lucien Brush

2009-12-01T23:59:59.000Z

139

Thermal Modeling, Characterization and Management of On-chip Networks  

E-Print Network (OSTI)

Due to the wire delay constraints in deep submicron technology and increasing demand for on-chip bandwidth, networks are becoming the pervasive interconnect fabric to connect processing elements on chip. With ever-increasing power density and cooling costs, the thermal impact of onchip networks needs to be urgently addressed.

Li Shang; Li-shiuan Peh; Amit Kumar; Niraj K. Jha

2004-01-01T23:59:59.000Z

140

FAQ 26-Are there any uses for depleted uranium?  

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

uses for depleted uranium? Are there any uses for depleted uranium? Several current and potential uses exist for depleted uranium. Depleted uranium could be mixed with highly...

Note: This page contains sample records for the topic "thermal depletion model" 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

PBL Stratiform Cloud Inhomogeneities Thermally Induced by the Orography: A Parameterization for Climate Models  

Science Conference Proceedings (OSTI)

This paper proposes a parameterization for use in climate models of the orographic variance and associated thermal circulation's impact on the macroscopic behavior of planetary boundary layer (PBL) stratiform clouds. Orographically induced ...

Rafael Terra

2004-03-01T23:59:59.000Z

142

Designing Safe Lithium-Ion Battery Packs Using Thermal Abuse Models (Presentation)  

DOE Green Energy (OSTI)

NREL and NASA developed a thermal-electrical model that resolves PTC and cell behavior under external shorting, now being used to evaluate safety margins of battery packs for spacesuit applications.

Pesaran, A. A.; Kim, G. H.; Smith, K.; Darcy, E.

2008-12-01T23:59:59.000Z

143

Specification of the Scale and Magnitude of Thermals Used to Initiate Convection in Cloud Models  

Science Conference Proceedings (OSTI)

Boundary layer similarity techniques are employed to specify the scale and intensity of a thermal perturbation used to initialize a cloud in a numerical cloud model. Techniques are outlined to specify the needed similarity variables from external ...

Richard T. McNider; Fred J. Kopp

1990-01-01T23:59:59.000Z

144

Thermal mass performance in residential construction : an energy analysis using a cube model  

E-Print Network (OSTI)

Given the pervasiveness of energy efficiency concerns in the built environment, this research aims to answer key questions regarding the performance of thermal mass construction. The work presents the Cube Model, a simplified ...

Ledwith, Alison C. (Alison Catherine)

2012-01-01T23:59:59.000Z

145

Lattice Boltzmann modeling of the effective thermal conductivity for fibrous materials  

E-Print Network (OSTI)

J. , M. Wang, and Z. Li, A lattice Boltzmann algorithm forA novel thermal model for the lattice Boltzmann method inS. and Doolen G.D. , Lattice Boltzmann method for fluid

Wang, Moran; He, Jihuan; Yu, Jianyong; Pan, Ning

2007-01-01T23:59:59.000Z

146

Modeling the solar thermal receiver for the CSPonD Project  

E-Print Network (OSTI)

The objective was to create an accurate steady state thermal model of a molten salt receiver prototype with a horizontal divider plate in the molten salt for Concentrated Solar Power on Demand (CSPonD). The purpose of the ...

Rees, Jennifer A. (Jennifer Anne)

2011-01-01T23:59:59.000Z

147

A model library of solar thermal electric components for the computer code TRNSYS  

Science Conference Proceedings (OSTI)

A new approach to modeling solar thermal electric plants using the TRNSYS simulation environment is discussed. The TRNSYS environment offers many advantages over currently used tools, including the option to more easily study the hybrid solar/fossil plant configurations that have been proposed to facilitate market penetration of solar thermal technologies. A component library developed for Rankine cycle, Brayton cycle, and solar system modeling is presented. A comparison between KPRO and TRNSYS results for a simple Rankine cycle show excellent correlation.

Pitz-Paal, R. [Deutsches Zentrum fuer Luft- und Raumfahrt e.V., Koeln (Germany). Solare Energietechnik; Jones, S. [Sandia National Labs., Albuquerque, NM (United States)

1998-07-01T23:59:59.000Z

148

Some thermal transport properties of the FPU model with quadratic pinning  

E-Print Network (OSTI)

Thermal transport properties of the FPU $\\beta$ model with a quadratic pinning term are investigated for various couplings and temperatures. In particular, the size dependence of the thermal conductivity, $\\kappa\\propto L^\\alpha$, is studied. $\\alpha$ agrees with that of the FPU $\\beta$ model (with no pinning) at high temperatures but decreases at low temperatures. This crossover behavior occurs at a temperature depending on the strength of the quadratic pinning.

Kenichiro Aoki

2008-01-02T23:59:59.000Z

149

Modeling and Analysis of CSP Systems (Fact Sheet), Thermal Systems...  

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

The models can also help analysts assess the potential market penetration and economic impact of CSP under different policy and deployment scenarios. The Solar Advisor Model (SAM)...

150

New thermal model with distinct freeze-out temperatures for baryons and mesons  

SciTech Connect

A significant amount of experimental data for particle production in high-energy heavy ion collisions (10 - 200 GeV/A at center of mass) has been accumulated during last years. Many different theoretical attempts have tried to describe these data using thermal models in the approximation of global thermal equilibrium considering only one freeze-out temperature. However the thermal models often are not able to describe adequately the whole multiplicities of hadrons. For instance, the abundance of strange particles is overestimate and the pion yields are underestimated. In this work is presented a thermal hadronic model with two different temperatures in order to describe the baryonic and mesonic chemical freeze-out in ultra-relativistic heavy ion collisions. The model is used to fit the particle population ratios of the hadrons produced in the reaction. The proposal is not merely to incorporate one additional degree of freedom in the adjustment procedure of data, but to present and alternative scenario for the freeze out stage in the collisional proces s. This new reformulated version of thermal model was applied to a set of data, offering a rather good improvement in the fitting of the calculated particle ratios to the data. The results suggest that the introduced model makes the thermal approach more robust to handle with a larger number of colliding systems and a more comprehensive set of reaction observables.

De Assis, Leonardo P. G.; Duarte, Sergio B. [Centro Brasileiro de Pesquisas Fisicas Dr. Xavier Sigaud 150, 22290-180 Rio de Janeiro-RJ (Brazil); Chiapparini, Marcelo [Instituto de Fisica, Universidade do Estado do Rio de Janeiro Rua Sao Francisco Xavier 524, 20 550-900 Rio de Janeiro-RJ (Brazil); Hirsch, Luciana R. [Departamento de Fisica, Universidade Tecnologica Federal do Parana Av. Sete de Setembro, 3165, 8 0230-901 Curitiba-PR (Brazil); Delfino, Antonio Jr. [Instituto de Fisica, Universidade Federal Fluminense Av. Gal. Milton Tavares de Souza, 24210-346 Niteroi-RJ (Brazil)

2013-05-06T23:59:59.000Z

151

Modeling the compressive deformation of metal micro-textured thermal interface materials using SEM geometry reconstruction  

Science Conference Proceedings (OSTI)

Idealized and simplified geometries are commonly used in finite element models to ease model creation and meshing. However, at smaller length-scales, the influence of geometrical imperfections and defects can significantly affect the accuracy of the ... Keywords: Buckling, Finite element modeling, Metal micro-textured thermal interface materials, Plastic deformation, SEM stereomicroscopy, Surface reconstruction

R. Kempers; P. Ahern; A. J. Robinson; A. M. Lyons

2012-02-01T23:59:59.000Z

152

Depleted UF6 Management Program Overview Presentation  

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

Depleted UF6 Management Program Overview Presentation Cylinders Photo Next Screen A Legacy of Uranium Enrichment...

153

A Geothermal Field Model Based On Geophysical And Thermal Prospectings In  

Open Energy Info (EERE)

Model Based On Geophysical And Thermal Prospectings In Model Based On Geophysical And Thermal Prospectings In Nea Kessani (Ne Greece) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: A Geothermal Field Model Based On Geophysical And Thermal Prospectings In Nea Kessani (Ne Greece) Details Activities (0) Areas (0) Regions (0) Abstract: The present study completes a study by Thanassoulas et al. (1986) Geophys. Prosp.34, 83-97 and deals with geophysical exploration for geothermal resources in Nea Kessani area, NE Greece. The results of some deep electrical soundings (AB = 6000 m) with the interpretation of a gravity profile crossing the investigated area are considered together with thermal investigations. All subsequent information, along with the conclusions of an earlier paper dealing with a reconnaissance geophysical

154

Hydrogen-burn survival: preliminary thermal model and test results  

DOE Green Energy (OSTI)

This report documents preliminary Hydrogen Burn Survival (HBS) Program experimental and analytical work conducted through February 1982. The effects of hydrogen deflagrations on safety-related equipment in nuclear power plant containment buildings are considered. Preliminary results from hydrogen deflagration experiments in the Sandia Variable Geometry Experimental System (VGES) are presented and analytical predictions for these tests are compared and discussed. Analytical estimates of component thermal responses to hydrogen deflagrations in the upper and lower compartments of an ice condenser, pressurized water reactor are also presented.

McCulloch, W.H.; Ratzel, A.C.; Kempka, S.N.; Furgal, D.T.; Aragon, J.J.

1982-08-01T23:59:59.000Z

155

A THERMAL EVOLUTION MODEL OF CENTAUR 10199 CHARIKLO  

SciTech Connect

Centaur 10199 Chariklo appears to have a varying spectral behavior. While three different spectral studies detect the presence of water ice at the surface, two more recent studies do not detect any absorption bands. In this article, we consider the possibility that Chariklo undergoes cometary activity that could be responsible for the observed spectral variations. We simulate its thermal evolution, finding that crystalline water ice should be present in the object core, and amorphous water ice should be found at the surface. Upon entering the inner solar system, Chariklo might experience some cometary activity due to ice crystallization if the obliquity is high, due to the adjustment of the internal structure to a new thermal equilibrium. No other activity is expected from this source, unless an external source like an impact provides the heat needed. In the case of such an event, we find that dust emitted in a coma is unlikely to be responsible for the observed spectral variations. In contrast, water ice grains in the coma would reproduce this pattern, meaning that the water ice detected after Chariklo's discovery was present in these grains and not on the object surface. Nonetheless, any activity would require an external additional heat source to be triggered, through an outburst, which might favor the spatial variations hypothesis.

Guilbert-Lepoutre, A., E-mail: aguilbert@ucla.edu [Department of Earth and Space Sciences, UCLA, Los Angeles, CA 90095 (United States)

2011-03-15T23:59:59.000Z

156

The Steady-State Atmospheric Circulation Response to Climate Change–like Thermal Forcings in a Simple General Circulation Model  

Science Conference Proceedings (OSTI)

The steady-state extratropical atmospheric response to thermal forcing is investigated in a simple atmospheric general circulation model. The thermal forcings qualitatively mimic three key aspects of anthropogenic climate change: warming in the ...

Amy H. Butler; David W. J. Thompson; Ross Heikes

2010-07-01T23:59:59.000Z

157

Computation of Thermal Fields with Non-Stationary Model at ...  

Science Conference Proceedings (OSTI)

Numerical experiments in the case of electron beam melting of different metals ... Multiscale Modeling of Nanoscale Precipitate Stability in Irradiated Materials.

158

Modelling Concentrating Solar Power with Thermal Energy Storage...  

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

limited energy available for either generation or storage. The modelled dispatch of CSP energy in PLEXOS is based on the hydro generation module, modified to incorporate the...

159

Numerical model to characterize the thermal comfort in new ecodistricts: methodology and validation through the canyon street case  

Science Conference Proceedings (OSTI)

In built-up areas, the urban structures affect the radiative and thermal environment. The numerical simulation models provide informations about urban thermal performance for many ranges of urban configurations. This paper presents a validation of a ... Keywords: CFD model, building heat transfers, coupling model, street canyon, thermo-radiative model

Khaled Athamena; Jean Francois Sini; Julien Guilhot; Jerome Vinet; Maeva Sabre; Jean-Michel Rosant

2011-01-01T23:59:59.000Z

160

Numerical model to characterize the thermal comfort in new eco-districts: methodology and validation through the canyon street case  

Science Conference Proceedings (OSTI)

In built-up areas, the urban structures affect the radiative and thermal environment. The numerical simulation models provide informations about urban thermal performance for many ranges of urban configurations. This paper presents a validation of a ... Keywords: CFD model, building heat transfers, coupling model, street canyon, thermo-radiative model

Khaled Athamena; Jean Francois Sini; Julien Guilhot; Jerome Vinet; Maeva Sabre; Jean-Michel Rosant

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "thermal depletion model" 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

A model for residual stress evolution in air-plasma-sprayed zirconia thermal barrier coatings  

Science Conference Proceedings (OSTI)

Ruby fluorescence spectroscopy indicates that residual stress in air-plasma-sprayed zirconia thermal barrier coatings is a function of the local interface geometry. The stress profile of a simulated rough interface characterized by ``peaks'' and ``valleys'' was modeled with a finite-element approach that accounted for thermal mismatch, oxide scale growth, and top coat sintering. Dependence of the stress profile on interface geometry and microstructure was investigated, and the results were compared with measured stresses.

Nair, B. G.; Singh, J. P.; Grimsditch, M.

2000-02-28T23:59:59.000Z

162

The creation of a courtyard microclimate thermal model for the analysis of courtyard houses  

E-Print Network (OSTI)

This research is an effort to revive the use of courtyard housing clusters in a modern context, which were traditionally known for their distinctive passive cooling performance. The goal is to promote energy efficient design in hot-arid climates and temperate climates by reviving the use of courtyard housing clusters. The objective is to introduce a simplified thermal model that simulates the courtyard microclimate, which has been tested with actual field data from a case study house. The case study house was an indigenous courtyard house in Cairo, Egypt that was built around 1400 AD, having an area of about 5000 sq. ft. (i.e., comparable to the size of a single-family house) with heavy thermal mass. To accomplish this, a finite difference thermal network model was created for simulating the case study courtyard microclimate. The finite difference (FD) model showed validity as it calibrated very well against field data. This model allowed running parametric sensitivity studies on the courtyard thermal simulation factors: air change rates, thermal mass, solar absorption, wall and floor emissivity, ground temperature, cloud cover, and ambient air temperature. The results of the parametric analysis showed that the model was sensitive to variations in the air change rates, solar absorptivity, and ambient air (rooftop) temperatures. The courtyard microclimate model was then used in combination with thermal simulation software (DOE-2) to analyze the thermal performance of the case study house, which was also validated with measured field data. The DOE-2 program showed limitations when applied to the case study, non-conditioned building, and showed a convergence deficiency when simulating high thermal mass buildings. The DOE-2 program did not perform well in simulating the impact of changes in thermal mass as compared to previous published field measurements. The proposed combinations of the FD microclimate/DOE-2 simulation did not perform as well as the FD microclimate simulation. The FD courtyard microclimate simulation model with onsite data for calibration is advantageous in introducing for the first time the ability to perform computer simulations on any number of proposed courtyard design alternatives for reaching optimum thermal performance.

Bagneid, Amr

2006-08-01T23:59:59.000Z

163

Three-dimensional Thermal and Airflow (3D-TAF) Model of a Dome-covered  

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

Three-dimensional Thermal and Airflow (3D-TAF) Model of a Dome-covered Three-dimensional Thermal and Airflow (3D-TAF) Model of a Dome-covered House in Canada Speaker(s): Yaolin Lin Date: October 6, 2009 - 12:00pm Location: 90-3122 A dome-covered house is an example of sustainable design that draws from biological forms in nature. A three-dimensional thermal and air flow (3D-TAF) model was developed to estimate the energy needs of a dome-covered house. This model has two components: a thermal model to calculate the temperature; and an air flow model to find the velocities, which are needed to estimate the surface convection. The two models are solved iteratively at every time step until they converge. I will present the numerical methods for solving the mathematical models, and compared the results with other simulated and experimental results from similar structures. I will

164

Modeling the subsurface thermal impact of Arctic thaw lakes in a warming climate  

Science Conference Proceedings (OSTI)

Warming air temperatures in the Arctic are modifying the rates of thermokarst processes along Alaska's Arctic Coastal Plain. The Arctic Coastal Plain is dominated by thaw lakes. These kilometer-scale lakes are the most visible surface features in the ... Keywords: MATLAB, Numerical model, Permafrost, Thaw lakes, Thermal model

N. Matell; R. S. Anderson; I. Overeem; C. Wobus; F. E. Urban; G. D. Clow

2013-04-01T23:59:59.000Z

165

Model for Naturally Ventilated Cavities on the Exteriors of Opaque Building Thermal Envelopes  

SciTech Connect

This paper describes a model for naturally ventilated cavities on the exterior of opaque building thermal envelopes that are formed by the presence of a lightweight baffle. The model can be used for building components that are slightly detached from the main envelope (but do not connect to the interior).

Griffith, B.

2006-11-01T23:59:59.000Z

166

Depletion effects of silicon deposition from methyltrichlorosilane  

DOE Green Energy (OSTI)

The deposition rate of SiC on carbon-coated Nicalon fibers from methyltrichlorosilane in hydrogen was measured as a function of temperature, pressure, total flow rate, and simulated reactant depletion. The results, which are included in this paper together with kinetic information on the stability of methyltrichlorosilane, led to two conclusions: two different mechanisms of deposition can occur depending on whether the methyltrichlorosilane has an opportunity to dissociate into separate silicon- and carbon-containing precursors, and the deposition rate is strongly reduced by the generation of byproduct HCl. The data were fitted to a simple etch model to obtain a kinetic expression that accounts for the significant effect of HCl.

Besmann, T.M.; Sheldon, B.W.; Moss, T.S. III; Kaster, M.D. (Oak Ridge National Lab., TN (United States))

1992-10-01T23:59:59.000Z

167

MATHEMATICAL MODELS OF THERMAL AND CHEMICAL TRANSPORT IN GEOLOGIC MEDIA  

E-Print Network (OSTI)

for Modeling Fluid and Heat Flow in Fractured Porous Media,Fluid Flow in a Single Fracture Because the topology of fractured media is different from that of porous media,

Lai, C.-H.

2010-01-01T23:59:59.000Z

168

Modeling the chemical, diffusional, and thermal processes of a microreactor  

E-Print Network (OSTI)

This thesis seeks to create a high fidelity model of the multiphysics present in a typical microreactor using propane combustion as a fuel source. The system is fully described by energy, momentum, and mass equations, all ...

Silva, James Emanuel

2012-01-01T23:59:59.000Z

169

Energy Balance Models Incorporating Transport of Thermal and Latent Energy  

Science Conference Proceedings (OSTI)

Standard latitudinally resolved energy balance models describe conservation of energy on a sphere subject to solar heating, cooling by infrared radiation and diffusive redistribution of energy according to a Fourier type heat flow with flux ...

Brian P. Flannery

1984-02-01T23:59:59.000Z

170

Magnetotelluric models of the Roosevelt Hot Springs thermal area, Utah  

DOE Green Energy (OSTI)

The Roosevelt Hot Springs (RHS) thermal area, which includes a hotwater-dominated fracture zone prospect, near the eastern margin of the Basin-Range tectonic province, conceivably possesses a whole family of resistivity structures that includes the following: deep hot brine reservoirs, deep-seated partially molten heat sources in the crust or upper mantle that drive the convective system, near-surface hydrothermal alteration zones, wet sedimentary fill in valleys, and a regional, apparently one-dimensional resistivity profile of the crust and upper mantle. This complex resistivity makeup, particular to RHS but probably similar to that at other geothermal areas in the Great Basin, must be treated as being fully three-dimensional (3-D). In an attempt to understand these structures, broadband (10/sup -3/ to 10/sup -2/ Hz) tensor magnetotelluric (MT) data were obtained including apparent resistivities (rho/sub a/), impedance phases (phi) and vertical magnetic field transfer functions for 93 sites in the vicinity of this resource area.

Wannamaker, P.E.; Ward, S.H.; Hohmann, G.W.; Sill, W.R.

1980-09-01T23:59:59.000Z

171

Potential Uses of Depleted Uranium  

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

POTENTIAL USES OF DEPLETED URANIUM POTENTIAL USES OF DEPLETED URANIUM Robert R. Price U.S. Department of Energy Germantown, Maryland 20874 M. Jonathan Haire and Allen G. Croff Chemical Technology Division Oak Ridge National Laboratory * Oak Ridge, Tennessee 37831-6180 June 2000 For American Nuclear Society 2000 International Winter and Embedded Topical Meetings Washington, D.C. November 12B16, 2000 The submitted manuscript has been authored by a contractor of the U.S. Government under contract DE-AC05-00OR22725. Accordingly, the U.S. Government retains a nonexclusive, royalty-free license to publish or reproduce the published form of this contribution, or allow others to do so, for U.S. Government purposes. _________________________

172

Measure of Diffusion Model Error for Thermal Radiation Transport  

E-Print Network (OSTI)

The diffusion approximation to the equation of transfer (Boltzmann transport equation) is usually applied to media where scattering dominates the interactions. Diffusion approximation helps in significant savings in terms of code complexity and computational time. However, this approximation often has significant error. Error due to the inherent nature of a physics model is called model error. Information about the model error associated with the diffusion approximation is clearly desirable. An indirect measure of model error is a quantity that is related in some way to the error but not equal to the error. In general, indirect measures of error are expected to be less costly than direct measures. Perhaps the most well-known indirect measure of the diffusion model error is the variable-Eddington tensor. This tensor provides a great deal of information about the angular dependence of the angular intensity solution, but it is not always simple to interpret. We define a new indirect measure of the diffusion model error called the diffusion model error source (DME source). When this DME source is added to the diffusion equation, the transport solution for the angular-integrated intensity is obtained. In contrast to the variable-Eddington tensor, our DME source is a scalar that is conceptually easy to interpret. In addition to defining the DME source analytically, we show how to generate this source numerically relative to the Sn radiative transfer equations with linear-discontinuous spatial discretization. This numerical source is computationally tested and shown to reproduce the Sn solution for a number of problems. Our radiative transfer model solves a coupled, time dependent, multi-frequency, 1-D slab equation and material heat transfer equation. We then use diffusion approximation to solve the same problem. The difference due to this approximation can be modelled by a “diffusion source”. The diffusion source is defined as an amount of inhomogeneous source that, when added to a diffusion calculation, gives a solution for the angle-integrated intensity that is equal to the transport solution.

Kumar, Akansha

2013-05-01T23:59:59.000Z

173

MAAP5 BWR Primary System Thermal-Hydraulics Model Enhancement Description  

Science Conference Proceedings (OSTI)

This report describes proposed enhancements to the Modular Accident Analysis Program (MAAP) reactor coolant system (RCS) thermal-hydraulics model for BWRs. MAAP is an EPRI-owned and -licensed computer program that simulates the operation of light water moderated nuclear power plants for both current and advanced light water reactor (ALWR) designs.EPRI introduced a new RCS model for PWRs in MAAP version 5.00. The new PWR RCS model includes mechanistic calculation of gas and water flows ...

2013-02-25T23:59:59.000Z

174

Simulation of Static Flying Attitudes with Different Heat Transfer Models for a Flying-Height Control Slider with Thermal Protrusion  

E-Print Network (OSTI)

Zhang, S. , Bogy, D.B. : A heat transfer model for thermal ?A phenomenological heat transfer model for the molecular gasWong, C.H. : A generalized heat transfer model for thin ?lm

Chen, Du; Bogy, David B.

2010-01-01T23:59:59.000Z

175

Analysis of Permafrost Thermal Dynamics and Response to Climate Change in the CMIP5 Earth System Models  

Science Conference Proceedings (OSTI)

The authors analyze global climate model predictions of soil temperature [from the Coupled Model Intercomparison Project phase 5 (CMIP5) database] to assess the models’ representation of current-climate soil thermal dynamics and their predictions ...

Charles D. Koven; William J. Riley; Alex Stern

2013-03-01T23:59:59.000Z

176

State-space modelling for heater induced thermal effects on LISA Pathfinder's Test Masses  

E-Print Network (OSTI)

The OSE (Offline Simulations Environment) simulator of the LPF (LISA Pathfinder) mission is intended to simulate the different experiments to be carried out in flight. Amongst these, the thermal diagnostics experiments are intended to relate thermal disturbances and interferometer readouts, thereby allowing the subtraction of thermally induced interferences from the interferometer channels. In this paper we report on the modelling of these simulated experiments, including the parametrisation of different thermal effects (radiation pressure effect, radiometer effect) that will appear in the Inertial Sensor environment of the LTP (LISA Technology Package). We report as well how these experiments are going to be implemented in the LTPDA toolbox, which is a dedicated tool for LPF data analysis that will allow full traceability and reproducibility of the analysis thanks to complete recording of the processes.

Ferran Gibert; Miquel Nofrarias; Marc Diaz-Aguiló; Alberto Lobo; Nikolaos Karnesis; Ignacio Mateos; Josep Sanjuán; Ivan Lloro; Lluís Gesa; Víctor Martín

2012-07-30T23:59:59.000Z

177

Reduced order models for thermal analysis : final report : LDRD Project No. 137807.  

SciTech Connect

This LDRD Senior's Council Project is focused on the development, implementation and evaluation of Reduced Order Models (ROM) for application in the thermal analysis of complex engineering problems. Two basic approaches to developing a ROM for combined thermal conduction and enclosure radiation problems are considered. As a prerequisite to a ROM a fully coupled solution method for conduction/radiation models is required; a parallel implementation is explored for this class of problems. High-fidelity models of large, complex systems are now used routinely to verify design and performance. However, there are applications where the high-fidelity model is too large to be used repetitively in a design mode. One such application is the design of a control system that oversees the functioning of the complex, high-fidelity model. Examples include control systems for manufacturing processes such as brazing and annealing furnaces as well as control systems for the thermal management of optical systems. A reduced order model (ROM) seeks to reduce the number of degrees of freedom needed to represent the overall behavior of the large system without a significant loss in accuracy. The reduction in the number of degrees of freedom of the ROM leads to immediate increases in computational efficiency and allows many design parameters and perturbations to be quickly and effectively evaluated. Reduced order models are routinely used in solid mechanics where techniques such as modal analysis have reached a high state of refinement. Similar techniques have recently been applied in standard thermal conduction problems e.g. though the general use of ROM for heat transfer is not yet widespread. One major difficulty with the development of ROM for general thermal analysis is the need to include the very nonlinear effects of enclosure radiation in many applications. Many ROM methods have considered only linear or mildly nonlinear problems. In the present study a reduced order model is considered for application to the combined problem of thermal conduction and enclosure radiation. The main objective is to develop a procedure that can be implemented in an existing thermal analysis code. The main analysis objective is to allow thermal controller software to be used in the design of a control system for a large optical system that resides with a complex radiation dominated enclosure. In the remainder of this section a brief outline of ROM methods is provided. The following chapter describes the fully coupled conduction/radiation method that is required prior to considering a ROM approach. Considerable effort was expended to implement and test the combined solution method; the ROM project ended shortly after the completion of this milestone and thus the ROM results are incomplete. The report concludes with some observations and recommendations.

Hogan, Roy E., Jr.; Gartling, David K.

2010-09-01T23:59:59.000Z

178

Depleted Uranium Uses Research and Development  

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

DU Uses DU Uses Depleted Uranium Uses Research & Development A Depleted Uranium Uses Research and Development Program was initiated to explore beneficial uses of depleted uranium (DU) and other materials resulting from conversion of depleted UF6. A Depleted Uranium Uses Research and Development Program was initiated to explore the safe, beneficial use of depleted uranium and other materials resulting from conversion of depleted UF6 (e.g., fluorine and empty carbon steel cylinders) for the purposes of resource conservation and cost savings compared with disposal. This program explored the risks and benefits of several depleted uranium uses, including uses as a radiation shielding material, a catalyst, and a semi-conductor material in electronic devices.

179

A thermal analysis model for high power density beam stops  

SciTech Connect

The Lawrence Berkeley National Laboratory (LBNL) is presently designing and building the 2.5 MeV injector for the Spallation Neutron Source (SNS). The design includes various beam intercepting devices such as beam stops and slits. The target power densities can be as high as 500 kW/cm{sup 2} with a beam stopping range of 25 to 30 microns, producing stresses well above yield in most materials. In order to analyze the induced temperatures and stresses, a finite element model has been developed. The model has been written parametrically to allow the beam characteristics, target material, dimensions, angle of incidence and mesh densities to be easily adjusted. The heat load is applied to the model through the use of a 3-dimensional table containing the calculated volumetric heat rates. The load is based on a bi-gaussian beam shape which is absorbed by the target according to a Bragg peak distribution. The results of several analyses using the SNS Front End beam are presented.

Virostek, S.; Oshatz, D.; Staples, J.

2001-06-08T23:59:59.000Z

180

A Mountain-Scale Thermal Hydrologic Model for Simulating Fluid Flow and Heat Transfer in Unsaturated Fractured Rock  

E-Print Network (OSTI)

Studies Using the Yucca Mountain Unsaturated Zone Model,Unsaturated Zone at Yucca Mountain, Nevada, to Thermal LoadUnsaturated Zone, Yucca Mountain, Nevada, Water-Resources

Wu, Yu-Shu; Mukhopadhyay, Sumit; Zhang, Keni; Bodvarsson, Gudmundur S.

2005-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "thermal depletion model" 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

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

E-Print Network (OSTI)

drift-scale thermal test at Yucca Mountain, Nevada. Lawrencemechanical analyses of the Yucca Mountain Drift Scale Test–waste repository at Yucca Mountain, Nevada. The modeling

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

2010-01-01T23:59:59.000Z

182

Simulating thermal explosion of RDX-based explosives: Model comparison with experiment  

DOE Green Energy (OSTI)

We compare two-dimensional model results with measurements for the thermal, chemical and mechanical behavior in a thermal explosion experiment. Confined high explosives are heated at a rate of 1 C per hour until an explosion is observed. The heating, ignition, and deflagration phases are modeled using an Arbitrarily Lagrangian-Eulerian code (ALE3D) that can handle a wide range of time scales that vary from a structural to a dynamic hydro time scale. During the pre-ignition phase, quasi-static mechanics and diffusive thermal transfer from a heat source to the HE are coupled with the finite chemical reactions that include both endothermic and exothermic processes. Once the HE ignites, a hydro dynamic calculation is performed as a burn front propagates through the HE. Two RDX-based explosives, C-4 and PBXN-109, are considered, whose chemical-thermal-mechanical models are constructed based on measurements of thermal and mechanical properties along with small scale thermal explosion measurements. The simulated dynamic response of HE confinement during the explosive phase is compared to measurements in large scale thermal explosion tests. The explosion temperatures for both HE's are predicted to within 5 C. Calculated and measured wall strains provide an indication of vessel pressurization during the heating phase and violence during the explosive phase. During the heating phase, simulated wall strains provide only an approximate representation of measured values indicating a better numerical treatment is needed to provide accurate results. The results also show that more numerical accuracy is needed for vessels with lesser confinement strength. For PBXN-109, the measured wall strains during the explosion are well represented by the ALE3D calculations.

Yoh, J J; McClelland, M A; Maienschein, J L; Wardell, J F; Tarver, C M

2004-10-11T23:59:59.000Z

183

Evaluation of the gas production economics of the gas hydrate cyclic thermal injection model  

SciTech Connect

The objective of the work performed under this directive is to assess whether gas hydrates could potentially be technically and economically recoverable. The technical potential and economics of recovering gas from a representative hydrate reservoir will be established using the cyclic thermal injection model, HYDMOD, appropriately modified for this effort, integrated with economics model for gas production on the North Slope of Alaska, and in the deep offshore Atlantic. The results from this effort are presented in this document. In Section 1, the engineering cost and financial analysis model used in performing the economic analysis of gas production from hydrates -- the Hydrates Gas Economics Model (HGEM) -- is described. Section 2 contains a users guide for HGEM. In Section 3, a preliminary economic assessment of the gas production economics of the gas hydrate cyclic thermal injection model is presented. Section 4 contains a summary critique of existing hydrate gas recovery models. Finally, Section 5 summarizes the model modification made to HYDMOD, the cyclic thermal injection model for hydrate gas recovery, in order to perform this analysis.

Kuuskraa, V.A.; Hammersheimb, E.; Sawyer, W.

1985-05-01T23:59:59.000Z

184

Lithium Depletion of Nearby Young Stellar Associations  

E-Print Network (OSTI)

We estimate cluster ages from lithium depletion in five pre-main-sequence groups found within 100 pc of the Sun: TW Hydrae Association, Eta Chamaeleontis Cluster, Beta Pictoris Moving Group, Tucanae-Horologium Association and AB Doradus Moving Group. We determine surface gravities, effective temperatures and lithium abundances for over 900 spectra through least squares fitting to model-atmosphere spectra. For each group, we compare the dependence of lithium abundance on temperature with isochrones from pre-main-sequence evolutionary tracks to obtain model dependent ages. We find that the Eta Chamaelontis Cluster and the TW Hydrae Association are the youngest, with ages of 12+/-6 Myr and 12+/-8 Myr, respectively, followed by the Beta Pictoris Moving Group at 21+/-9 Myr, the Tucanae-Horologium Association at 27+/-11 Myr, and the AB Doradus Moving Group at an age of at least 45 Myr (where we can only set a lower limit since the models -- unlike real stars -- do not show much lithium depletion beyond this age). Here, the ordering is robust, but the precise ages depend on our choice of both atmospheric and evolutionary models. As a result, while our ages are consistent with estimates based on Hertzsprung-Russell isochrone fitting and dynamical expansion, they are not yet more precise. Our observations do show that with improved models, much stronger constraints should be feasible: the intrinsic uncertainties, as measured from the scatter between measurements from different spectra of the same star, are very low: around 10 K in effective temperature, 0.05 dex in surface gravity, and 0.03 dex in lithium abundance.

Erin Mentuch; Alexis Brandeker; Marten H. van Kerkwijk; Ray Jayawardhana; Peter H. Hauschildt

2008-08-26T23:59:59.000Z

185

AQUIFER THERMAL ENERGY STORAGE  

E-Print Network (OSTI)

aquifers for thermal energy storage. Problems outlined aboveModeling of Thermal Energy Storage in Aquifers," Proceed-ings of Aquifer Thermal Energy Storage Workshop, Lawrence

Tsang, C.-F.

2011-01-01T23:59:59.000Z

186

AQUIFER THERMAL ENERGY STORAGE  

E-Print Network (OSTI)

using aquifers for thermal energy storage. Problems outlinedmatical Modeling of Thermal Energy Storage in Aquifers,"Proceed- ings of Aquifer Thermal Energy Storage Workshop,

Tsang, C.-F.

2011-01-01T23:59:59.000Z

187

Thermal Structure and Airflow in a Model Simulation of an Occluded Marine Cyclone  

Science Conference Proceedings (OSTI)

A very fine mesh model simulation of the Ocean Ranger storm of February 1982 is used to study the thermal structure and airflow in an intense marine cyclone. In particular, the study investigates the structures of the occluded front and the ...

Ying-Hwa Kuo; Richard J. Reed; Simon Low-Nam

1992-10-01T23:59:59.000Z

188

Nondestructive Evaluation: Probabilistic Reliability Model for Thermally Aged Cast Austenitic Stainless Steel Piping  

Science Conference Proceedings (OSTI)

A probabilistic fracture mechanics (PFM) method has been developed to support the evaluation of the effects of thermal aging embrittlement on the reliability of reactor coolant cast austenitic stainless steel (CASS) piping components. The probabilistic method relies on modeling of the contributing elements of a deterministic analysis (for example, geometry, loading conditions, materials, and known degradation ...

2012-12-12T23:59:59.000Z

189

Modelling of the Uncertainty of Nuclear Fuel Thermal Behaviour Using the URANIE Framework  

Science Conference Proceedings (OSTI)

In the global framework of nuclear fuel behaviour simulation, the response of the models describing the physical phenomena occurring during the irradiation in reactor is mainly conditioned by the confidence in the calculated temperature of the fuel. ... Keywords: uncertainty, thermal behaviour, nuclear fuel, URANIE

Antoine Boulore; Christine Struzik; Fabrice Gaudier

2009-09-01T23:59:59.000Z

190

Three-dimensional Thermal and Airflow (3D-TAF) Model of a Dome...  

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

Three-dimensional Thermal and Airflow (3D-TAF) Model of a Dome-covered House in Canada Speaker(s): Yaolin Lin Date: October 6, 2009 - 12:00pm Location: 90-3122 A dome-covered house...

191

THERMALIZATION OF THE ION KINETIC ENERGY IN A Ne GAS PUFF PINCH MODEL*  

E-Print Network (OSTI)

THERMALIZATION OF THE ION KINETIC ENERGY IN A Ne GAS PUFF PINCH MODEL* J. L. Giuliani, J. W Department of Energy/NNSA, Washington DC USA Full understanding of the dynamics, population kinetics, and energy budget of a K-shell radiating Z-pinch remains a challenging problem in high energy density plasma

192

Model for Thermal Behavior of Shaded Photovoltaic Cells under Hot-Spot Condition  

Science Conference Proceedings (OSTI)

We address the problem of modeling the thermal behavior of photovoltaic (PV) cells that, due to their being exposed to shading, may experience a dramatic temperature increase (a phenomenon referred to as hot-spot) with consequent reduction of the provided ... Keywords: solar cell, hot-spot heating, energy efficiency, reliability

Daniele Giaffreda; Martin Omana; Daniele Rossi; Cecilia Metra

2011-10-01T23:59:59.000Z

193

Model development and calibration for the coupled thermal, hydraulic and mechanical phenomena of the bentonite  

E-Print Network (OSTI)

FOR THE COUPLED THERMAL, HYDRAULIC AND MECHANICAL PHENOMENAby the interdependence of thermal, hydraulic and mechanical

Hernelind, J.

2009-01-01T23:59:59.000Z

194

Modeling of thermally driven hydrological processes in partially saturated fractured rock  

Science Conference Proceedings (OSTI)

This paper is a review of the research that led to an in-depth understanding of flow and transport processes under strong heat stimulation in fractured, porous rock. It first describes the anticipated multiple processes that come into play in a partially saturated, fractured porous volcanic tuff geological formation, when it is subject to a heat source such as that originating from the decay of radionuclides. The rationale is then given for numerical modeling being a key element in the study of multiple processes that are coupled. The paper outlines how the conceptualization and the numerical modeling of the problem evolved, progressing from the simplified to the more realistic. Examples of numerical models are presented so as to illustrate the advancement and maturation of the research over the last two decades. The most recent model applied to in situ field thermal tests is characterized by (1) incorporation of a full set of thermal-hydrological processes into a numerical simulator, (2) realistic representation of the field test geometry, in three dimensions, and (3) use of site-specific characterization data for model inputs. Model predictions were carried out prior to initiation of data collection, and the model results were compared to diverse sets of measurements. The approach of close integration between modeling and field measurements has yielded a better understanding of how coupled thermal hydrological processes produce redistribution of moisture within the rock, which affects local permeability values and subsequently the flow of liquid and gases. The fluid flow in turn will change the temperature field. We end with a note on future research opportunities, specifically those incorporating chemical, mechanical, and microbiological factors into the study of thermal and hydrological processes.

Tsang, Yvonne; Birkholzer, Jens; Mukhopadhyay, Sumit

2009-03-15T23:59:59.000Z

195

Analysis of Heat Dissipation in Li-Ion Cells & Modules for Modeling of Thermal Runaway (Presentation)  

DOE Green Energy (OSTI)

The objectives of this study are: (1) To develop 3D Li-Ion battery thermal abuse ''reaction'' models for cell and module analysis; (2) To understand the mechanisms and interactions between heat transfer and chemical reactions during thermal runaway for Li-Ion cells and modules; (3) To develop a tool and methodology to support the design of abuse-tolerant Li-Ion battery systems for PHEVs/HEVs; and (4) To help battery developers accelerate delivery of abuse-tolerant Li-Ion battery systems in support of the FreedomCAR's Energy Storage Program.

Kim, G.-H.; Pesaran, A.

2007-05-15T23:59:59.000Z

196

Phase-field modeling of temperature gradient driven pore migration coupling with thermal conduction  

SciTech Connect

Pore migration in a temperature gradient (Soret effect) is investigated by a phase-field model coupled with a heat transfer calculation. Pore migration is observed towards the high temperature domain with velocities that agree with analytical solution. Due to the low thermal conductivity of the pores, the temperature gradient across individual pores is increased, which in turn, accelerates the pore migration. In particular, for pores filled with xenon and helium, the pore velocities are increased by a factor of 2.2 and 2.1, respectively. A quantitative equation is then derived to predict the influence of the low thermal conductivity of pores.

Liangzhe Zhang; Michael R Tonks; Paul C Millett; Yongfeng Zhang; Karthikeyan Chockalingam; Bulent Biner

2012-04-01T23:59:59.000Z

197

Improving the Noah Land Surface Model in Arid Regions with an Appropriate Parameterization of the Thermal Roughness Length  

Science Conference Proceedings (OSTI)

Daytime land surface temperatures in arid and semiarid regions are typically not well simulated in current land surface models (LSMs). This study first evaluates the importance of parameterizing the thermal roughness length (z0h) to model the ...

Yingying Chen; Kun Yang; Degang Zhou; Jun Qin; Xiaofeng Guo

2010-08-01T23:59:59.000Z

198

Beryllium Impregnation of Uranium Fuel: Thermal Modeling of Cylindrical Objects for Efficiency Evaluation  

E-Print Network (OSTI)

With active research projects related to nuclear waste immobilization and high conductivity nuclear fuels, a thermal model has been developed to simulate the temperature profile within a heat generating cylinder in order to imitate the behavior of each design. This work is being done so that it may be used in future research projects to represent how heat is being stored or dissipated in a material that has a uniformly distributed heat source from fission or radiation deposition. The model has been built to have a 2-D visual representation of the temperature distribution. A nodal system is employed for this model so that the user chooses the size of the mesh that will develop an accurate reading for their purposes. The model uses fundamental heat transfer equations and heat conduction properties for different metals. The heat transfer equations that will be used are fundamental and used at each point in the mesh developed by the user to ensure accuracy of the calculation. Below is such an example of an equation that will be used to model the temperature distribution in the cylindrical samples. By choosing the thermal properties associated with the material that is being researched, certain parameters are imposed in the equations automatically. This provides an easy method to see changes in the temperature distribution due to the improvements that have been made. Such parameters are the thermal conductivity and the thermal diffusivity along with others such as the material specific heat. The model will incorporate color variations in the display in order to allow larger meshes to be used while not diminishing the appearance of the results. The color variation will be due to a gradient from red to blue to represent hot to cold.

Lynn, Nicholas

2011-08-04T23:59:59.000Z

199

THERMAL MODEL CALIBRATION FOR MINOR PLANETS OBSERVED WITH WIDE-FIELD INFRARED SURVEY EXPLORER/NEOWISE  

SciTech Connect

With the Wide-field Infrared Survey Explorer (WISE), we have observed over 157,000 minor planets. Included in these are a number of near-Earth objects, main-belt asteroids, and irregular satellites which have well measured physical properties (via radar studies and in situ imaging) such as diameters. We have used these objects to validate models of thermal emission and reflected sunlight using the WISE measurements, as well as the color corrections derived in Wright et al. for the four WISE bandpasses as a function of effective temperature. We have used 50 objects with diameters measured by radar or in situ imaging to characterize the systematic errors implicit in using the WISE data with a faceted spherical near-Earth asteroid thermal model (NEATM) to compute diameters and albedos. By using the previously measured diameters and H magnitudes with a spherical NEATM model, we compute the predicted fluxes (after applying the color corrections given in Wright et al.) in each of the four WISE bands and compare them to the measured magnitudes. We find minimum systematic flux errors of 5%-10%, and hence minimum relative diameter and albedo errors of {approx}10% and {approx}20%, respectively. Additionally, visible albedos for the objects are computed and compared to the albedos at 3.4 {mu}m and 4.6 {mu}m, which contain a combination of reflected sunlight and thermal emission for most minor planets observed by WISE. Finally, we derive a linear relationship between subsolar temperature and effective temperature, which allows the color corrections given in Wright et al. to be used for minor planets by computing only subsolar temperature instead of a faceted thermophysical model. The thermal models derived in this paper are not intended to supplant previous measurements made using radar or spacecraft imaging; rather, we have used them to characterize the errors that should be expected when computing diameters and albedos of minor planets observed by WISE using a spherical NEATM model.

Mainzer, A.; Masiero, J.; Bauer, J.; Ressler, M.; Eisenhardt, P. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States); Grav, T. [Department of Physics and Astronomy, Johns Hopkins University, 366 Bloomberg Center, 3400 N. Charles Street, Baltimore, MD 21218 (United States); Wright, E. [UCLA Astronomy, P.O. Box 91547, Los Angeles, CA 90095-1547 (United States); Cutri, R. M. [Infrared Processing and Analysis Center, California Institute of Technology, Pasadena, CA 91125 (United States); McMillan, R. S. [Lunar and Planetary Laboratory, University of Arizona, 1629 East University Blvd., Kuiper Space Science Bldg. 92, Tucson, AZ 85721-0092 (United States); Cohen, M., E-mail: amainzer@jpl.nasa.gov [Radio Astronomy Laboratory, 601 Campbell Hall, University of California, Berkeley, CA 94720 (United States)

2011-08-01T23:59:59.000Z

200

Results from a workshop on research needs for modeling aquifer thermal energy storage systems  

DOE Green Energy (OSTI)

A workshop an aquifer thermal energy storage (ATES) system modeling was conducted in Seattle, Washington, on November 30 and December 1, 1989 by Pacific Northwest Laboratory (PNL). The goal of the workshop was to develop a list of high-priority research activities that would facilitate the commercial success of ATES. During the workshop, participants reviewed currently available modeling tools for ATES systems and produced a list of significant issues related to modeling ATES systems. Participants assigned a priority to each issue on the list by voting and developed a list of research needs for each of four high-priority research areas; the need for a feasibility study model, the need for engineering design models, the need for aquifer characterization, and the need for an economic model. The workshop participants concluded that ATES commercialization can be accelerated by aggressive development of ATES modeling tools and made specific recommendations for that development. 2 tabs.

Drost, M K

1990-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "thermal depletion model" 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

Depleted uranium disposal options evaluation  

SciTech Connect

The Department of Energy (DOE), Office of Environmental Restoration and Waste Management, has chartered a study to evaluate alternative management strategies for depleted uranium (DU) currently stored throughout the DOE complex. Historically, DU has been maintained as a strategic resource because of uses for DU metal and potential uses for further enrichment or for uranium oxide as breeder reactor blanket fuel. This study has focused on evaluating the disposal options for DU if it were considered a waste. This report is in no way declaring these DU reserves a ``waste,`` but is intended to provide baseline data for comparison with other management options for use of DU. To PICS considered in this report include: Retrievable disposal; permanent disposal; health hazards; radiation toxicity and chemical toxicity.

Hertzler, T.J.; Nishimoto, D.D.; Otis, M.D. [Science Applications International Corp., Idaho Falls, ID (United States). Waste Management Technology Div.

1994-05-01T23:59:59.000Z

202

Depleted Argon from Underground Sources  

Science Conference Proceedings (OSTI)

Argon is a strong scintillator and an ideal target for Dark Matter detection; however {sup 39}Ar contamination in atmospheric argon from cosmic ray interactions limits the size of liquid argon dark matter detectors due to pile-up. Argon from deep underground is depleted in {sup 39}Ar due to the cosmic ray shielding of the earth. In Cortez, Colorado, a CO{sub 2} well has been discovered to contain approximately 600 ppm of argon as a contamination in the CO{sub 2}. We first concentrate the argon locally to 3% in an Ar, N{sub 2}, and He mixture, from the CO{sub 2} through chromatographic gas separation, and then the N{sub 2} and He will be removed by continuous distillation to purify the argon. We have collected 26 kg of argon from the CO{sub 2} facility and a cryogenic distillation column is under construction at Fermilab to further purify the argon.

Back, H. O.; Galbiati, C.; Goretti, A.; Loer, B.; Montanari, D.; Mosteiro, P. [Department of Physics, Princeton University, Jadwin Hall, Princeton, NJ 08544 (United States); Alexander, T.; Alton, A.; Rogers, H. [Augustana College, Physics Department, 2001 South Summit Ave., Sioux Fall, SD 57197 (United States); Kendziora, C.; Pordes, S. [Fermi National Accelerator Laboratory, P.O. Box 500, Batavia, IL 60510 (United States)

2011-04-27T23:59:59.000Z

203

SEASONAL THERMAL ENERGY STORAGE IN AQUIFERS-MATHEMATICAL MODELING STUDIES IN 1979  

E-Print Network (OSTI)

Aspects of Aquifer Thermal Energy Storage." Lawrencethe Auburn University Thermal Energy Storage Experiment."LBL~l0208 SEASONAL THERMAL ENERGY STORAGE IN AQUIFERS~

Tsang, Chin Fu

2013-01-01T23:59:59.000Z

204

Ozone depletion, greenhouse gases, and climate change: Proceedings  

SciTech Connect

This symposium was primarily concerned with the linkages between ozone depletion and increasing greenhouse gases and with their combined effect in causing climate change to occur on a global scale. The presentations in these proceedings review the current state of knowledge about stratospheric ozone depletion, discuss the probable effect of predicted greenhouse gas increase on future ozone trends, summarize observational data on changing atmospheric chemistry and associated atmospheric temperatures, and describe the continuing effort to model and predict future scenarios of climatic change relative to ozone and greenhouse gases in both the stratosphere and the troposphere. Some of the questions and answers that followed the presentations have been included when they highlight noteworthy points that were not covered in the presentation itself. The request by the National Climate Program Office for a symposium on the above related issues is included. The symposium agenda and participants are given. As well as a glossary of special terms and abbreviations. In summary, the Joint Symposium on Ozone Depletion, Greenhouse Gases, and Climate Change reviewed the magnitude and causes of stratospheric ozone depletion and examined the connections that exist between this problem and the impending climate warming to increasing greenhouse gases. The presentations of these proceedings indicate that the connections are real and important, and that the stratospheric ozone depletion and tropospheric greenhouse warming problems must be studied as parts of an interactive global system rather than as more or less unconnected events.

1989-01-01T23:59:59.000Z

205

The depleted hydrogen atoms in chemical graph theory  

Science Conference Proceedings (OSTI)

A new algorithm which explicitly describes the depleted hydrogen atoms is proposed for chemical graph computations, and especially for molecular connectivity model studies. The new algorithm continues to be centred on the concepts of complete graphs ... Keywords: General chemical graphs, complete graphs, hydrogen perturbation, molecular connectivity computations

Lionello Pogliani

2008-12-01T23:59:59.000Z

206

High-voltage-compatible, fully depleted CCDs  

SciTech Connect

We describe charge-coupled device (CCD) developmentactivities at the Lawrence Berkeley National Laboratory (LBNL).Back-illuminated CCDs fabricated on 200-300 mu m thick, fully depleted,high-resistivity silicon substrates are produced in partnership with acommercial CCD foundry.The CCDs are fully depleted by the application ofa substrate bias voltage. Spatial resolution considerations requireoperation of thick, fully depleted CCDs at high substrate bias voltages.We have developed CCDs that are compatible with substrate bias voltagesof at least 200V. This improves spatial resolution for a given thickness,and allows for full depletion of thicker CCDs than previously considered.We have demonstrated full depletion of 650-675 mu m thick CCDs, withpotential applications in direct x-ray detection. In this work we discussthe issues related to high-voltage operation of fully depleted CCDs, aswell as experimental results on high-voltage-compatible CCDs.

Holland, Stephen E.; Bebek, Chris J.; Dawson, Kyle S.; Emes, JohnE.; Fabricius, Max H.; Fairfield, Jessaym A.; Groom, Don E.; Karcher, A.; Kolbe, William F.; Palaio, Nick P.; Roe, Natalie A.; Wang, Guobin

2006-05-15T23:59:59.000Z

207

,"Natural Gas Depleted Fields Storage Capacity "  

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

Depleted Fields Storage Capacity " ,"Click worksheet name or tab at bottom for data" ,"Worksheet Name","Description"," Of Series","Frequency","Latest Data for" ,"Data 1","Natural...

208

Grid orientation effects in the simulation of cold water injection into depleted vapor zones  

DOE Green Energy (OSTI)

A considerable body of field experience with injection has been accumulated at Larderello, Italy and The Geysers, California; the results have been mixed. There are well documented cases where injection has increased flow rates of nearby wells. Return of injected fluid as steam from production wells has been observed directly through chemical and isotopic changes of produced fluids (Giovannoni et al., 1981; Nuti et al., 1981). In other cases injection has caused thermal interference and has degraded the temperature and pressure of production wells. Water injection into depleted vapor zones gives rise to complex two-phase fluid flow and heat transfer processes with phase change. These are further complicated by the fractured-porous nature of the reservoir rocks. An optimization of injection design and operating practice is desirable; this requires realistic and robust mathematical modeling capabilities.

Pruess, K.

1991-01-01T23:59:59.000Z

209

Algebraic Turbulent Heat Flux Model for Prediction of Thermal Stratification in Piping Systems  

Science Conference Proceedings (OSTI)

Technical Paper / Special Issue on the 14th International Topical Meeting on Nuclear Reactor Thermal Hydraulics (NURETH-14) / Thermal Hydraulics

M. Pellegrini; H. Endo; E. Merzari; H. Ninokata

210

Numerical Modeling of the Transient Thermal Interference of Vertical U-Tube Haet Exchangers  

E-Print Network (OSTI)

Non-linear finite element models were developed to simulate transient heat and mass transfer in the soil surrounding the ground heat exchangers of ground-coupled heat pumps (GCHPs) operating in the cooling mode. Parametric studies were performed with two dimensional horizontal cross sectional models. The heat transfer and temperature distributions yielded excess errors less than 6% and 3%, respectively, when compared to analytical solutions. Two constant temperature sources performed equivalent heating as one constant temperature source having twice the radius. For constant heat flux sources, the equivalent radius was found to be increased by ?2. A heat flux equivalent radius (tau_h,eqv) was developed and shown to be more consistent than the geometric radius (tau_g,eqv). All equivalent radii varied with time and source separation. A heat exchanger effectiveness for two sources, (epsilon_A), was introduced based on an earlier definition for one source. Effectiveness was found to be independent of a dimensionless temperature variable that included temperatures of the tubes and soil, and varied only with separation distance at steady state. Thermal short circuiting was defined as 1 – epsilon_A and ranged from 38% to 47% in the reasonable installation separation range. Non-homogenous media were modeled by varying backfill thermal conductivity. Maximum heat transfer was achieved with a fictitious backfill thermal conductivity of 1,000 W/m-K, while measured bentonite backfill conductivities were less than 2 W/m-K. The overall heat transfer increased with backfill thermal conductivity but epsilon_A decreased. Therefore, the backfill effectiveness of Couvillion was used to rank backfill performance. The range of the backfill effectiveness was from 45% for touching bentonite backfill tubes to 60% for the fictitious backfill at a separation of seven l/Do. Moisture migration was incorporated into the numerical finite element model by formulating coupled partial differential equations for non-linear heat and mass transfer. Simulations with decreasing soil moisture contents resulted in lower thermal conductivity and performance degradation. Increasing the bore hole size improved the efficiency (decreased thermal short circuiting) by as much as 20%. In addition, higher conductivity fictitious backfills improved efficiency by up to an additional 20%. However, cost savings in both cases had a negligible effect compared to the bore hole cost.

Muraya, Norman K.

1994-12-01T23:59:59.000Z

211

A comparison of two heat transfer models for estimating thermal drawdown in Hot Dry Rock reservoirs  

DOE Green Energy (OSTI)

Estimates of thermal drawdown in Hot Dry Rock geothermal systems have been made with two different models of heat transfer from hydraulically fractured reservoir rock blocks to water circulated through the fracture permeability. One model is based on deconvolution of experimental tracer response curves into a network of flowpaths connected in parallel with heat transfer calculated individually in each flowpath. The second model is based on one-dimensional flow through the rock with a block size distribution described as a group of equivalent-radius spheres for which the heat transfer equations can be solved analytically. The two-models were applied to the planned Phase II long-term thermal drawdown experiment at Fenton Hill, NM. The results show good agreement between the two models, with estimates of temperature cooldown from 240/sup 0/C to 150/sup 0/C in a few years depending on selected operation parameters, but with somewhat differing cooldown curve characteristic shapes. Data from the long-term experiment will be helpful in improving the two models.

Robinson, B.A.; Kruger, P.

1988-01-01T23:59:59.000Z

212

Simulating the Value of Concentrating Solar Power with Thermal Energy Storage in a Production Cost Model  

SciTech Connect

Concentrating solar power (CSP) deployed with thermal energy storage (TES) provides a dispatchable source of renewable energy. The value of CSP with TES, as with other potential generation resources, needs to be established using traditional utility planning tools. Production cost models, which simulate the operation of grid, are often used to estimate the operational value of different generation mixes. CSP with TES has historically had limited analysis in commercial production simulations. This document describes the implementation of CSP with TES in a commercial production cost model. It also describes the simulation of grid operations with CSP in a test system consisting of two balancing areas located primarily in Colorado.

Denholm, P.; Hummon, M.

2012-11-01T23:59:59.000Z

213

Depleted Uranium De-conversion  

E-Print Network (OSTI)

This Environmental Report (ER) constitutes one portion of an application being submitted by International Isotopes Fluorine Products (IIFP) to construct and operate a facility that will utilize depleted DUF6 to produce high purity inorganic fluorides, uranium oxides, and anhydrous hydrofluoric acid. The proposed IIFP facility will be located near Hobbs, New Mexico. IIFP has prepared the ER to meet the requirements specified in 10 CFR 51, Subpart A, particularly those requirements set forth in 10 CFR 51.45(b)-(e). The organization of this ER is generally consistent with NUREG-1748, “Environmental Review Guidance for Licensing Actions Associated with NMSS Programs, Final Report.” The Environmental Report for this proposed facility provides information that is specifically required by the NRC to assist it in meeting its obligations under the National Environmental Policy Act (NEPA) of 1969 and the agency’s NEPA-implementing regulations. This ER demonstrates that the environmental protection measures proposed by IIFP are adequate to protect both the environment and the health and safety of the public. This Environmental Report evaluates the potential environmental impacts of the Proposed Action and its reasonable alternatives. This ER also describes the environment potentially affected by IIEF’s proposal,

Fluorine Extraction Process

2009-01-01T23:59:59.000Z

214

Depleted argon from underground sources  

Science Conference Proceedings (OSTI)

Argon is a powerful scintillator and an excellent medium for detection of ionization. Its high discrimination power against minimum ionization tracks, in favor of selection of nuclear recoils, makes it an attractive medium for direct detection of WIMP dark matter. However, cosmogenic {sup 39}Ar contamination in atmospheric argon limits the size of liquid argon dark matter detectors due to pile-up. The cosmic ray shielding by the earth means that Argon from deep underground is depleted in {sup 39}Ar. In Cortez Colorado a CO{sub 2} well has been discovered to contain approximately 500ppm of argon as a contamination in the CO{sub 2}. In order to produce argon for dark matter detectors we first concentrate the argon locally to 3-5% in an Ar, N{sub 2}, and He mixture, from the CO{sub 2} through chromatographic gas separation. The N{sub 2} and He will be removed by continuous cryogenic distillation in the Cryogenic Distillation Column recently built at Fermilab. In this talk we will discuss the entire extraction and purification process; with emphasis on the recent commissioning and initial performance of the cryogenic distillation column purification.

Back, H.O.; /Princeton U.; Alton, A.; /Augustana U. Coll.; Calaprice, F.; Galbiati, C.; Goretti, A.; /Princeton U.; Kendziora, C.; /Fermilab; Loer, B.; /Princeton U.; Montanari, D.; /Fermilab; Mosteiro, P.; /Princeton U.; Pordes, S.; /Fermilab

2011-09-01T23:59:59.000Z

215

FAQ 7-How is depleted uranium produced?  

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

How is depleted uranium produced? How is depleted uranium produced? How is depleted uranium produced? Depleted uranium is produced during the uranium enrichment process. In the United States, uranium is enriched through the gaseous diffusion process in which the compound uranium hexafluoride (UF6) is heated and converted from a solid to a gas. The gas is then forced through a series of compressors and converters that contain porous barriers. Because uranium-235 has a slightly lighter isotopic mass than uranium-238, UF6 molecules made with uranium-235 diffuse through the barriers at a slightly higher rate than the molecules containing uranium-238. At the end of the process, there are two UF6 streams, with one stream having a higher concentration of uranium-235 than the other. The stream having the greater uranium-235 concentration is referred to as enriched UF6, while the stream that is reduced in its concentration of uranium-235 is referred to as depleted UF6. The depleted UF6 can be converted to other chemical forms, such as depleted uranium oxide or depleted uranium metal.

216

THE RIMINI PROTOCOL Oil Depletion Protocol  

E-Print Network (OSTI)

Soaring oil prices have drawn attention to the issue of the relative supply and demand for crude oil. This fact alone tells us that oil is a finite resource, which in turn means that it is subject to depletion1 THE RIMINI PROTOCOL an Oil Depletion Protocol ~ Heading Off Economic Chaos and Political Conflict

Keeling, Stephen L.

217

A two dimensional thermal network model for a photovoltaic solar wall  

Science Conference Proceedings (OSTI)

A two dimensional thermal network model is proposed to predict the temperature distribution for a section of photovoltaic solar wall installed in an outdoor room laboratory in Concordia University, Montreal, Canada. The photovoltaic solar wall is constructed with a pair of glass coated photovoltaic modules and a polystyrene filled plywood board as back panel. The active solar ventilation through a photovoltaic solar wall is achieved with an exhaust fan fixed in the outdoor room laboratory. The steady state thermal network nodal equations are developed for conjugate heat exchange and heat transport for a section of a photovoltaic solar wall. The matrix solution procedure is adopted for formulation of conductance and heat source matrices for obtaining numerical solution of one dimensional heat conduction and heat transport equations by performing two dimensional thermal network analyses. The temperature distribution is predicted by the model with measurement data obtained from the section of a photovoltaic solar wall. The effect of conduction heat flow and multi-node radiation heat exchange between composite surfaces is useful for predicting a ventilation rate through a solar ventilation system. (author)

Dehra, Himanshu [1-140 Avenue Windsor, Lachine, Quebec (Canada)

2009-11-15T23:59:59.000Z

218

A Transient Model of Induced Natural Circulation Thermal Cycling for Hydrogen Isotope Separation  

SciTech Connect

The property of selective temperature dependence of adsorption and desorption of hydrogen isotopes by palladium is used for isotope separation. A proposal to use natural circulation of nitrogen to alternately heat and cool a packed bed of palladium coated beads is under active investigation, and a device consisting of two interlocking natural convection loops is being designed. A transient numerical model of the device has been developed to aid the design process. It is a one-dimensional finite-difference model, using the Boussinesq approximation. The thermal inertia of the pipe walls and other heat structures as well as the heater control logic is included in the model. Two system configurations were modeled and results are compared.

SHADDAY, MARTIN

2005-07-12T23:59:59.000Z

219

Physics and modeling of thermal flow and soil mechanics in unconsolidated porous media  

SciTech Connect

This paper describes a new formulation of nonlinear soil mechanics and multiphase thermal flow. The nonlinearites of the soil behavior and their interactions with fluid flow causing shear failure of the soil are the dominant features of the process. The numerical formulation of the coupled flow/stress solution model includes nonlinear compressibility and flow properties as functions of pressure, stress, and temperature; nonlinear, incremental, thermal poroelastic stress analysis; and shear or tensile failure and its effects on transport properties, porosity, and stress. An efficient sequential numerical scheme was developed. It is mass conservative and applicable to external coupling of existing simulators. The 1D examples show some startling new features of reservoir mechanics in unconsolidated media.

Settari, A. (Simtech Consulting Services Ltd. (US))

1992-02-01T23:59:59.000Z

220

Technical support document for proposed revision of the model energy code thermal envelope requirements  

SciTech Connect

This report documents the development of the proposed revision of the council of American Building Officials` (CABO) 1993 supplement to the 1992 Model Energy Code (MEC) (referred to as the 1993 MEC) building thermal envelope requirements for single-family and low-rise multifamily residences. The goal of this analysis was to develop revised guidelines based on an objective methodology that determined the most cost-effective (least total life-cycle cost [LCC]) combination of energy conservation measures (ECMs) for residences in different locations. The ECMs with the lowest LCC were used as a basis for proposing revised MEC maximum U{sub o}-value (thermal transmittance) curves in the MEC format. The changes proposed here affect the requirements for ``group R`` residences. The group R residences are detached one- and two-family dwellings (referred to as single-family) and all other residential buildings three stories or less (referred to as multifamily).

Conner, C.C.; Lucas, R.G.

1993-02-01T23:59:59.000Z

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221

Technical support document for proposed revision of the model energy code thermal envelope requirements  

SciTech Connect

This report documents the development of the proposed revision of the council of American Building Officials' (CABO) 1993 supplement to the 1992 Model Energy Code (MEC) (referred to as the 1993 MEC) building thermal envelope requirements for single-family and low-rise multifamily residences. The goal of this analysis was to develop revised guidelines based on an objective methodology that determined the most cost-effective (least total life-cycle cost [LCC]) combination of energy conservation measures (ECMs) for residences in different locations. The ECMs with the lowest LCC were used as a basis for proposing revised MEC maximum U[sub o]-value (thermal transmittance) curves in the MEC format. The changes proposed here affect the requirements for group R'' residences. The group R residences are detached one- and two-family dwellings (referred to as single-family) and all other residential buildings three stories or less (referred to as multifamily).

Conner, C.C.; Lucas, R.G.

1993-02-01T23:59:59.000Z

222

Thermal performance of clean horizontal radiant barriers under winter conditions: Laboratory measurements and mathematical modeling  

Science Conference Proceedings (OSTI)

Several field experiments have been performed on attic radiant barriers under winter conditions; however, most of them have been confined to the fairly mild climates of Florida, Oklahoma, and Tennessee. Only one field experiment in a very cold climate (Canada) has been performed. In addition, no previous laboratory experiments under winter conditions have been performed on an attic both with and without a radiant barrier. This paper presents the results of laboratory measurements of the thermal performance of clean horizontal radiant barriers in a simulated residential attic module under nighttime or low solar gain daytime winter conditions. Comparing tests under the same conditions with and without a radiant barrier shows that the addition of a clean horizontal radiant barrier to insulation at the R-22 to R-25 level decreases the ceiling heat flow by 6 to 8%. The experimental results were found to be in very good agreement with predictions made with a mathematical model for the thermal performance of attics.

Wilkes, K.E.; Childs, P.W.

1992-01-01T23:59:59.000Z

223

Thermal performance of clean horizontal radiant barriers under winter conditions: Laboratory measurements and mathematical modeling  

Science Conference Proceedings (OSTI)

Several field experiments have been performed on attic radiant barriers under winter conditions; however, most of them have been confined to the fairly mild climates of Florida, Oklahoma, and Tennessee. Only one field experiment in a very cold climate (Canada) has been performed. In addition, no previous laboratory experiments under winter conditions have been performed on an attic both with and without a radiant barrier. This paper presents the results of laboratory measurements of the thermal performance of clean horizontal radiant barriers in a simulated residential attic module under nighttime or low solar gain daytime winter conditions. Comparing tests under the same conditions with and without a radiant barrier shows that the addition of a clean horizontal radiant barrier to insulation at the R-22 to R-25 level decreases the ceiling heat flow by 6 to 8%. The experimental results were found to be in very good agreement with predictions made with a mathematical model for the thermal performance of attics.

Wilkes, K.E.; Childs, P.W.

1992-08-01T23:59:59.000Z

224

Characterization of the Thermal Structure inside an Urban Canyon: Field Measurements and Validation of a Simple Model  

Science Conference Proceedings (OSTI)

The results of measurement campaigns are analyzed to investigate the thermal structure in an urban canyon and to validate a simplified model simulating the air and surface temperatures from surface energy budgets. Starting from measurements at ...

Lorenzo Giovannini; Dino Zardi; Massimiliano de Franceschi

2013-01-01T23:59:59.000Z

225

Tropical Oceanic Response to Extratropical Thermal Forcing in a Coupled Climate Model: A Comparison between the Atlantic and Pacific Oceans  

Science Conference Proceedings (OSTI)

The tropical oceanic response to the extratropical thermal forcing is quantitatively estimated in a coupled climate model. This work focuses on comparison of the responses between the tropical Atlantic and Pacific. Under the same extratropical ...

Haijun Yang; Lu Wang

2011-08-01T23:59:59.000Z

226

Thermally Driven Flows at an Asymmetric Valley Exit: Observations and Model Studies at the Lech Valley Exit  

Science Conference Proceedings (OSTI)

The summertime thermal circulation in the region of an asymmetric valley exit is investigated by means of observations and high-resolution model simulations. The northeastward-oriented Alpine Lech Valley opening into the Bavarian Alpine foreland ...

Thomas Spengler; Jan H. Schween; Markus Ablinger; Günther Zängl; Joseph Egger

2009-10-01T23:59:59.000Z

227

Baroclinic Adjustment in an Atmosphere–Ocean Thermally Coupled Model: The Role of the Boundary Layer Processes  

Science Conference Proceedings (OSTI)

Baroclinic eddy equilibration and the roles of different boundary layer processes in limiting the baroclinic adjustment are studied using an atmosphere–ocean thermally coupled model. Boundary layer processes not only affect the dynamical ...

Yang Zhang; Peter H. Stone

2011-11-01T23:59:59.000Z

228

Efficient thermal management for multiprocessor systems  

E-Print Network (OSTI)

2.2.4 Thermal Modeling . . . . . . . .63 Table 4.3: Thermal Hot Spots . . . . . . . . . . . . . .Performance-Efficient Thermal Management . . . . . . . . . .

Co?kun, Ay?e K?v?lc?m

2009-01-01T23:59:59.000Z

229

The effect of simplifying the building description on the numerical modeling of its thermal performance  

SciTech Connect

A thermal building simulation program is a numerical model that calculates the response of the building envelopes to weather and human activity, simulates dynamic heating and cooling loads, and heating and cooling distribution systems, and models building equipment operation. The scope of the research is to supply the users of such programs with information about the dangers and benefits of simplifying the input to their models. The Introduction describes the advantages of modeling the heat transfer mechanisms in a building. The programs that perform this type of modeling have, however, limitations. The user is therefore often put in the situation of simplifying the floor plans of the building under study, but not being able to check the effects that this approximation introduces in the results of the simulation. Chapter 1 is a description of methods. It also introduces the floor plans for the office building under study and the ``reasonable`` floor plans simplifications. Chapter 2 presents DOE-2, the thermal building simulation program used in the sensitivity study. The evaluation of the accuracy of the DOE-2 program itself is also presented. Chapter 3 contains the sensitivity study. The complicated nature of the process of interpreting the temperature profile inside a space leads to the necessity of defining different building modes. The study compares the results from the model of the detailed building description with the results from the models of the same building having simplified floor plans. The conclusion is reached that a study of the effects of simplifying the floor plans of a building is important mainly for defining the cases in which this approximation is acceptable. Different results are obtained for different air conditioning/load regimes of the building. 9 refs., 24 figs.

Stetiu, C.

1993-07-01T23:59:59.000Z

230

Thermal-hydraulic model of a solid-oxide fuel cell. [17. 5 watts  

DOE Green Energy (OSTI)

A mathematical model has been developed to simulate the electrochemistry and thermal hydraulics in a monolithic solid oxide fuel cell (MSOFC). Dividing a single cell layer into a number of nodes, the model sets up the steady-state heat and mass transfer equations for each node in a cell layer. Based on the average thermal and compositional conditions at each node and a specified cell voltage, the model calculates the Nernst potential and the resultant current, heat generation, and heat removal rates at each node. These calculations yield the temperature and the fuel and oxidant compositions and partial pressure matrices for the entire cell. The simulation also provides related performance data for the fuel cell stack, such as energy efficiency, fuel utilization, and power density. The model can be used to simulate operation with different fuel gases, such as hydrogen, coal gas, and methanol reformate. A mathematical model such as this can be used to examine the effects of changing one or more of the various design variables and to evaluate the effectiveness of fabrication improvements in technology development. In the design phase, the model can be used to determine the size of the stack that will be required for a given power rating and to make design decisions regarding structure-specific parameters, such as the thicknesses of the anode, electrolyte, cathode, and interconnect layers and dimensions of the flow channels in the anode and the cathode. The model can also be helpful to the fuel cell system operator. For example, given a particular stack, the most favorable operating conditions can be determined by determining a priori the effects of altering process variables, such as flow rates and feed conditions. 6 refs., 12 figs., 3 tabs.

Ahmed, S.; Kumar, R.

1990-01-01T23:59:59.000Z

231

Validation and Calibration of Nuclear Thermal Hydraulics Multiscale Multiphysics Models - Subcooled Flow Boiling Study  

SciTech Connect

In addition to validation data plan, development of advanced techniques for calibration and validation of complex multiscale, multiphysics nuclear reactor simulation codes are a main objective of the CASL VUQ plan. Advanced modeling of LWR systems normally involves a range of physico-chemical models describing multiple interacting phenomena, such as thermal hydraulics, reactor physics, coolant chemistry, etc., which occur over a wide range of spatial and temporal scales. To a large extent, the accuracy of (and uncertainty in) overall model predictions is determined by the correctness of various sub-models, which are not conservation-laws based, but empirically derived from measurement data. Such sub-models normally require extensive calibration before the models can be applied to analysis of real reactor problems. This work demonstrates a case study of calibration of a common model of subcooled flow boiling, which is an important multiscale, multiphysics phenomenon in LWR thermal hydraulics. The calibration process is based on a new strategy of model-data integration, in which, all sub-models are simultaneously analyzed and calibrated using multiple sets of data of different types. Specifically, both data on large-scale distributions of void fraction and fluid temperature and data on small-scale physics of wall evaporation were simultaneously used in this work’s calibration. In a departure from traditional (or common-sense) practice of tuning/calibrating complex models, a modern calibration technique based on statistical modeling and Bayesian inference was employed, which allowed simultaneous calibration of multiple sub-models (and related parameters) using different datasets. Quality of data (relevancy, scalability, and uncertainty) could be taken into consideration in the calibration process. This work presents a step forward in the development and realization of the “CIPS Validation Data Plan” at the Consortium for Advanced Simulation of LWRs to enable quantitative assessment of the CASL modeling of Crud-Induced Power Shift (CIPS) phenomenon, in particular, and the CASL advanced predictive capabilities, in general. This report is prepared for the Department of Energy’s Consortium for Advanced Simulation of LWRs program’s VUQ Focus Area.

Anh Bui; Nam Dinh; Brian Williams

2013-09-01T23:59:59.000Z

232

Simulating HFIR Core Thermal Hydraulics Using 3D-2D Model Coupling  

SciTech Connect

A model utilizing interdimensional variable coupling is presented for simulating the thermal hydraulic interactions of the High Flux Isotope Reactor (HFIR) core at Oak Ridge National Laboratory (ORNL). The model s domain consists of a single, explicitly represented three-dimensional fuel plate and a simplified two-dimensional coolant channel slice. In simplifying the coolant channel, and thus the number of mesh points in which the Navier-Stokes equations must be solved, the computational cost and solution time are both greatly reduced. In order for the reduced-dimension coolant channel to interact with the explicitly represented fuel plate, however, interdimensional variable coupling must be enacted along all shared boundaries. The primary focus of this paper is in detailing the collection, storage, passage, and application of variables across this interdimensional interface. Comparisons are made showing the general speed-up associated with this simplified coupled model.

Travis, Adam R [ORNL] ORNL; Freels, James D [ORNL] ORNL; Ekici, Kivanc [ORNL] ORNL

2013-01-01T23:59:59.000Z

233

A STUDY OF ATES THERMAL BEHAVIOR USING A STEADY FLOW MODEL  

E-Print Network (OSTI)

and Warman, J.c. , "Thermal energy storage in a confinedIn Proceedings of Thermal Energy Storage in Aquifersand Tsang, c.F. , ~Aquifer thermal energy storage- parameter

Doughty, Christine

2013-01-01T23:59:59.000Z

234

Lithium depletion and the rotational history of exoplanet host stars  

E-Print Network (OSTI)

Israelian et al. (2004) reported that exoplanet host stars are lithium depleted compared to solar-type stars without detected massive planets, a result recently confirmed by Gonzalez (2008). We investigate whether enhanced lithium depletion in exoplanet host stars may result from their rotational history. We have developed rotational evolution models for slow and fast solar-type rotators from the pre-main sequence (PMS) to the age of the Sun and compare them to the distribution of rotational periods observed for solar-type stars between 1 Myr and 5 Gyr. We show that slow rotators develop a high degree of differential rotation between the radiative core and the convective envelope, while fast rotators evolve with little core-envelope decoupling. We suggest that strong differential rotation at the base of the convective envelope is responsible for enhanced lithium depletion in slow rotators. We conclude that lithium-depleted exoplanet host stars were slow rotators on the zero-age main sequence (ZAMS) and argue that slow rotation results from a long lasting star-disk interaction during the PMS. Altogether, this suggests that long-lived disks (> 5 Myr) may be a necessary condition for massive planet formation/migration.

Jerome Bouvier

2008-08-28T23:59:59.000Z

235

Thermal characterization and model free kinetics of aged epoxies and foams using TGA and DSC methods.  

SciTech Connect

Two classes of materials, poly(methylene diphenyl diisocyanate) or PMDI foam, and cross-linked epoxy resins, were characterized using thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC), to help understand the effects of aging and %E2%80%9Cbake-out%E2%80%9D. The materials were evaluated for mass loss and the onset of decomposition. In some experiments, volatile materials released during heating were analyzed via mass spectroscopy. In all, over twenty materials were evaluated to compare the mass loss and onset temperature for decomposition. Model free kinetic (MFK) measurements, acquired using variable heating rate TGA experiments, were used to calculate the apparent activation energy of thermal decomposition. From these compiled data the effects of aging, bake-out, and sample history on the thermal stability of materials were compared. No significant differences between aged and unaged materials were detected. Bake-out did slightly affect the onset temperature of decomposition but only at the highest bake-out temperatures. Finally, some recommendations for future handling are made.

Cordaro, Joseph Gabriel; Kruizenga, Alan Michael; Nissen, April

2013-10-01T23:59:59.000Z

236

THERMAL PERFORMANCE SENSITIVITY STUDIES IN SUPPORT OF MATERIAL MODELING FOR EXTENDED STORAGE OF USED NUCLEAR FUEL  

SciTech Connect

The work reported here is an investigation of the sensitivity of component temperatures of a storage system, including fuel cladding temperatures, in response to age-related changes that could degrade the design-basis thermal behavior of the system. Three specific areas of interest were identified for this study. • degradation of the canister backfill gas from pure helium to a mixture of air and helium, resulting from postulated leakage due to stress corrosion cracking (SCC) of canister welds • changes in surface emissivity of system components, resulting from corrosion or other aging mechanisms, which could cause potentially significant changes in temperatures and temperature distributions, due to the effect on thermal radiation exchange between components • changes in fuel and basket temperatures due to changes in fuel assembly position within the basket cells in the canister The purpose of these sensitivity studies is to provide a realistic example of how changes in the physical properties or configuration of the storage system components can affect temperatures and temperature distributions. The magnitudes of these sensitivities can provide guidance for identifying appropriate modeling assumptions for thermal evaluations extending long term storage out beyond 50, 100, 200, and 300 years.

Cuta, Judith M.; Suffield, Sarah R.; Fort, James A.; Adkins, Harold E.

2013-08-15T23:59:59.000Z

237

CRDIAC: Coupled Reactor Depletion Instrument with Automated Control  

SciTech Connect

When modeling the behavior of a nuclear reactor over time, it is important to understand how the isotopes in the reactor will change, or transmute, over that time. This is especially important in the reactor fuel itself. Many nuclear physics modeling codes model how particles interact in the system, but do not model this over time. Thus, another code is used in conjunction with the nuclear physics code to accomplish this. In our code, Monte Carlo N-Particle (MCNP) codes and the Multi Reactor Transmutation Analysis Utility (MRTAU) were chosen as the codes to use. In this way, MCNP would produce the reaction rates in the different isotopes present and MRTAU would use cross sections generated from these reaction rates to determine how the mass of each isotope is lost or gained. Between these two codes, the information must be altered and edited for use. For this, a Python 2.7 script was developed to aid the user in getting the information in the correct forms. This newly developed methodology was called the Coupled Reactor Depletion Instrument with Automated Controls (CRDIAC). As is the case in any newly developed methodology for modeling of physical phenomena, CRDIAC needed to be verified against similar methodology and validated against data taken from an experiment, in our case AFIP-3. AFIP-3 was a reduced enrichment plate type fuel tested in the ATR. We verified our methodology against the MCNP Coupled with ORIGEN2 (MCWO) method and validated our work against the Post Irradiation Examination (PIE) data. When compared to MCWO, the difference in concentration of U-235 throughout Cycle 144A was about 1%. When compared to the PIE data, the average bias for end of life U-235 concentration was about 2%. These results from CRDIAC therefore agree with the MCWO and PIE data, validating and verifying CRDIAC. CRDIAC provides an alternative to using ORIGEN-based methodology, which is useful because CRDIAC's depletion code, MRTAU, uses every available isotope in its depletion, unlike ORIGEN, which only depletes the isotopes specified by the user. This means that depletions done by MRTAU more accurately reflect reality. MRTAU also allows the user to build new isotope data sets, which means any isotope with nuclear data could be depleted, something that would help predict the outcomes of nuclear reaction testing in materials other than fuel, like beryllium or gold.

Steven K. Logan

2012-08-01T23:59:59.000Z

238

An X-ray Reprocessing Model of Disk Thermal Emission in Type 1 Seyfert Galaxies  

E-Print Network (OSTI)

Using a geometry consisting of a hot central Comptonizing plasma surrounded by a thin accretion disk, we model the optical through hard X-ray spectral energy distributions of the type 1 Seyfert galaxies NGC 3516 and NGC 7469. As in the model proposed by Poutanen, Krolik, & Ryde for the X-ray binary Cygnus X-1 and later applied to Seyfert galaxies by Zdziarski, Lubi\\'nski, & Smith, feedback between the radiation reprocessed by the disk and the thermal Comptonization emission from the hot central plasma plays a pivotal role in determining the X-ray spectrum, and as we show, the optical and ultraviolet spectra as well. Seemingly uncorrelated optical/UV and X-ray light curves, similar to those which have been observed from these objects can be explained by variations in the size, shape, and temperature of the Comptonizing plasma. Furthermore, by positing a disk mass accretion rate which satisfies a condition for global energy balance between the thermal Comptonization luminosity and the power available from accretion, one can predict the spectral properties of the hard X-ray continuum above $\\sim 50$ keV in type 1 Seyfert galaxies. Forthcoming measurements of the hard X-ray continuum by more sensitive hard X-ray and soft $\\gamma$-ray telescopes, in conjunction with simultaneous optical, UV, and soft X-ray monitoring, will allow the mass accretion rates to be directly constrained for these sources in the context of this model.

James Chiang

2002-02-12T23:59:59.000Z

239

SEASONAL THERMAL ENERGY STORAGE IN AQUIFERS-MATHEMATICAL MODELING STUDIES IN 1979  

E-Print Network (OSTI)

of Aquifer Thermal Energy Storage." Lawrence BerkeleyP, Andersen, "'rhermal Energy Storage in a Confined Aquifer~University Thermal Energy Storage Experiment." Lawrence

Tsang, Chin Fu

2013-01-01T23:59:59.000Z

240

Attainable Burnup in a LIFE Engine Loaded with Depleted Uranium  

Science Conference Proceedings (OSTI)

The Laser Inertial Fusion-based Energy (LIFE) system uses a laser-based fusion source for electricity production. The (D,T) reaction, beside a pure fusion system, allows the option to drive a sub-critical fission blanket in order to increase the total energy gain. In a typical fusion-fission LIFE engine the fission blanket is a spherical shell around the fusion source, preceded by a beryllium shell for neutron multiplications by means of (n,2n) reactions. The fuel is in the form of TRISO particles dispersed in carbon pebbles, cooled by flibe. The optimal design features 80 cm thick blanket, 16 cm multiplier, and 20% TRISO packing factor. A blanket loaded with depleted uranium and depleted in a single batch with continuous mixing can achieve burnup as high as {approx}85% FIMA while generating 2,000 MW of total thermal power and producing enough tritium to be used for fusion. A multi-segment blanket with a central promotion shuffling scheme enhances burnup to {approx}90% FIMA, whereas a blanket that is operated with continuous refueling achieves only 82% FIMA under the same constraints of thermal power and tritium self-sufficiency. Both, multi-segment and continuous refueling eliminate the need for a fissile breeding phase.

Fratoni, M; Kramer, K J; Latkowski, J F

2009-11-30T23:59:59.000Z

Note: This page contains sample records for the topic "thermal depletion model" 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

Depleted uranium: A DOE management guide  

Science Conference Proceedings (OSTI)

The U.S. Department of Energy (DOE) has a management challenge and financial liability in the form of 50,000 cylinders containing 555,000 metric tons of depleted uranium hexafluoride (UF{sub 6}) that are stored at the gaseous diffusion plants. The annual storage and maintenance cost is approximately $10 million. This report summarizes several studies undertaken by the DOE Office of Technology Development (OTD) to evaluate options for long-term depleted uranium management. Based on studies conducted to date, the most likely use of the depleted uranium is for shielding of spent nuclear fuel (SNF) or vitrified high-level waste (HLW) containers. The alternative to finding a use for the depleted uranium is disposal as a radioactive waste. Estimated disposal costs, utilizing existing technologies, range between $3.8 and $11.3 billion, depending on factors such as applicability of the Resource Conservation and Recovery Act (RCRA) and the location of the disposal site. The cost of recycling the depleted uranium in a concrete based shielding in SNF/HLW containers, although substantial, is comparable to or less than the cost of disposal. Consequently, the case can be made that if DOE invests in developing depleted uranium shielded containers instead of disposal, a long-term solution to the UF{sub 6} problem is attained at comparable or lower cost than disposal as a waste. Two concepts for depleted uranium storage casks were considered in these studies. The first is based on standard fabrication concepts previously developed for depleted uranium metal. The second converts the UF{sub 6} to an oxide aggregate that is used in concrete to make dry storage casks.

NONE

1995-10-01T23:59:59.000Z

242

Uranio impoverito: perch'e? (Depleted uranium: why?)  

E-Print Network (OSTI)

In this paper we develop a simple model of the penetration process of a long rod through an uniform target. Applying the momentum and energy conservation laws, we derive an analytical relation which shows how the penetration depth depends upon the density of the rod, given a fixed kinetic energy. This work was sparked off by the necessity of the author of understanding the reasons of the effectiveness of high density penetrators (e.g. depleted uranium penetrators) as anti-tank weapons.

D'Abramo, G

2003-01-01T23:59:59.000Z

243

An X-ray Reprocessing Model of Disk Thermal Emission in Type 1 Seyfert Galaxies  

E-Print Network (OSTI)

Using a geometry consisting of a hot central Comptonizing plasma surrounded by a thin accretion disk, we model the optical through hard X-ray spectral energy distributions of the type 1 Seyfert galaxies NGC 3516 and NGC 7469. As in the model proposed by Poutanen, Krolik, & Ryde for the X-ray binary Cygnus X-1 and later applied to Seyfert galaxies by Zdziarski, Lubi\\'nski, & Smith, feedback between the radiation reprocessed by the disk and the thermal Comptonization emission from the hot central plasma plays a pivotal role in determining the X-ray spectrum, and as we show, the optical and ultraviolet spectra as well. Seemingly uncorrelated optical/UV and X-ray light curves, similar to those which have been observed from these objects can be explained by variations in the size, shape, and temperature of the Comptonizing plasma. Furthermore, by positing a disk mass accretion rate which satisfies a condition for global energy balance between the thermal Comptonization luminosity and the power available fr...

Chiang, J

2002-01-01T23:59:59.000Z

244

Thermal and Gamma-ray induced relaxation in As-S glasses: modeling and experiment  

SciTech Connect

Enthalpy relaxation is measured in a series of As-S glasses irradiated with gamma rays and these samples are compared with a set of identical control samples kept in the dark. It is shown that gamma irradiation lifts the kinetic barrier for relaxation at room temperature and speeds up the enthalpy release. The measured values of thermal relaxation in the dark agree closely with modeling results obtained by fitting differential scanning calorimetry curves with the TNM equations. The measured values of activation energy for enthalpy relaxation are also in close agreement with that predicted by the TNM model therefore lending credence to the fitting results. These measurements permit extraction of the effect of gamma irradiation on the glass structure for a series of As-S glasses with increasing structural coordination, and gamma irradiation is shown to reduce the structural relaxation time. It is also shown that lower coordination glasses exhibit greater radiation sensitivity but also greater thermal relaxation due to their lower Tg. On the other end, over-coordinated glasses show lower relaxation and almost no radiation sensitivity. This behavior is similar to the glass response under sub-bandgap light irradiation.

Lucas, Pierre; King, Ellyn A.; Erdmann, Robert G.; Riley, Brian J.; Sundaram, S. K.; McCloy, John S.

2011-09-09T23:59:59.000Z

245

Separating the Dynamical Effects of Climate Change and Ozone Depletion. Part II: Southern Hemisphere Troposphere  

Science Conference Proceedings (OSTI)

The separate effects of ozone depleting substances (ODSs) and greenhouse gases (GHGs) on forcing circulation changes in the Southern Hemisphere extratropical troposphere are investigated using a version of the Canadian Middle Atmosphere Model (...

Charles McLandress; Theodore G. Shepherd; John F. Scinocca; David A. Plummer; Michael Sigmond; Andreas I. Jonsson; M. Catherine Reader

2011-03-01T23:59:59.000Z

246

An evaporation-based model of thermal neutron induced ternary fission of plutonium  

E-Print Network (OSTI)

Ternary fission probabilities for thermal neutron induced fission of plutonium are analyzed within the framework of an evaporation-based model where the complexity of time-varying potentials, associated with the neck collapse, are included in a simplistic fashion. If the nuclear temperature at scission and the fission-neck-collapse time are assumed to be ~1.2 MeV and ~10^-22 s, respectively, then calculated relative probabilities of ternary-fission light-charged-particle emission follow the trends seen in the experimental data. The ability of this model to reproduce ternary fission probabilities spanning seven orders of magnitude for a wide range of light-particle charges and masses implies that ternary fission is caused by the coupling of an evaporation-like process with the rapid re-arrangement of the nuclear fluid following scission.

J. P. Lestone

2007-03-10T23:59:59.000Z

247

Seasonal thermal energy storage in unsaturated soils: Model development and field validation  

DOE Green Energy (OSTI)

This report summarizes ten years of activity carried out at the Earth Sciences Division of the Lawrence Berkeley Laboratory (LBI) in the subject of seasonal storage of thermal energy in unsaturated soils. The objectives of the work were to make a conceptual study of this type of storage, to offer guidelines for planning and evaluation of the method, to produce models and simulation for an actual field experiment, to participate in an on-line data analysis of experimental results. and to evaluate the results in terms of the validation of the concept, models and the experimental techniques. The actual field experiments were performed in Beer-Sheva, Israel. Details of engineering and field operations are not included in this report.

Doughty, C.; Nir, Aharon, Tsang, Chin-Fu

1991-06-01T23:59:59.000Z

248

Thermal-radiation heat-transfer model for degraded cores. [PWR; BWR  

SciTech Connect

One consequence of the accident at the Three Mile Island Unit 2 (TMI-2) nuclear power plant is a realization by the nuclear power technical community that there is a need for calculational tools that can be used to analyze the TMI-2 accident and to investigate hypothetical situations involving degraded light-water reactor (LWR) cores. As a result, there are now several ongoing modeling and code development efforts in the United States among which is the development of the MIMAS (Multifield Integrated Meltdown Analysis System code) at the Los Alamos National Laboratory. This paper describes a thermal-radiation heat-transfer model for LWR degraded cores that has been developed for the MIMAS code.

Tomkins, J.L.

1983-01-01T23:59:59.000Z

249

A Weighted Point Model for the Thermal Neutron Multiplicity Assay of High-Mass Plutonium Samples  

Science Conference Proceedings (OSTI)

A weighted point model for thermal neutron multiplicity counting has been developed for the assay of impure plutonium metal samples. Weighting factors are introduced for the spontaneous fission and ({alpha},n) contributions to the doubles and triples rates to account for the variations in neutron multiplication in these samples. The weighting factors are obtained from Monte Carlo simulations using the MCNPX code, which supports the simulation of spontaneous fission sources and can tally the source and detected neutron multiplicity distributions. Systematic behavior of the weighting factors was studied as a function of sample mass and geometry. Simulations were performed to evaluate the potential accuracy of assays performed with weighted point model analysis. Comparisons with experimental data are presented. The possible use of quads rates is explored.

M.S. Krick; W.H. Geist; D.R. Mayo

2005-10-01T23:59:59.000Z

250

An efficient modeling method for thermal stratification simulation in a BWR suppression pool  

SciTech Connect

The suppression pool in a BWR plant not only is the major heat sink within the containment system, but also provides major emergency cooling water for the reactor core. In several accident scenarios, such as LOCA and extended station blackout, thermal stratification tends to form in the pool after the initial rapid venting stage. Accurately predicting the pool stratification phenomenon is important because it affects the peak containment pressure; and the pool temperature distribution also affects the NPSHa (Available Net Positive Suction Head) and therefore the performance of the pump which draws cooling water back to the core. Current safety analysis codes use 0-D lumped parameter methods to calculate the energy and mass balance in the pool and therefore have large uncertainty in prediction of scenarios in which stratification and mixing are important. While 3-D CFD methods can be used to analyze realistic 3D configurations, these methods normally require very fine grid resolution to resolve thin substructures such as jets and wall boundaries, therefore long simulation time. For mixing in stably stratified large enclosures, the BMIX++ code has been developed to implement a highly efficient analysis method for stratification where the ambient fluid volume is represented by 1-D transient partial differential equations and substructures such as free or wall jets are modeled with 1-D integral models. This allows very large reductions in computational effort compared to 3-D CFD modeling. The POOLEX experiments at Finland, which was designed to study phenomena relevant to Nordic design BWR suppression pool including thermal stratification and mixing, are used for validation. GOTHIC lumped parameter models are used to obtain boundary conditions for BMIX++ code and CFD simulations. Comparison between the BMIX++, GOTHIC, and CFD calculations against the POOLEX experimental data is discussed in detail.

Haihua Zhao; Ling Zou; Hongbin Zhang; Hua Li; Walter Villanueva; Pavel Kudinov

2012-09-01T23:59:59.000Z

251

Simulation of Thermal Stratification in BWR Suppression Pools with One Dimensional Modeling Method  

Science Conference Proceedings (OSTI)

The suppression pool in a boiling water reactor (BWR) plant not only is the major heat sink within the containment system, but also provides the major emergency cooling water for the reactor core. In several accident scenarios, such as a loss-of-coolant accident and extended station blackout, thermal stratification tends to form in the pool after the initial rapid venting stage. Accurately predicting the pool stratification phenomenon is important because it affects the peak containment pressure; the pool temperature distribution also affects the NPSHa (available net positive suction head) and therefore the performance of the Emergency Core Cooling System and Reactor Core Isolation Cooling System pumps that draw cooling water back to the core. Current safety analysis codes use zero dimensional (0-D) lumped parameter models to calculate the energy and mass balance in the pool; therefore, they have large uncertainties in the prediction of scenarios in which stratification and mixing are important. While three-dimensional (3-D) computational fluid dynamics (CFD) methods can be used to analyze realistic 3-D configurations, these methods normally require very fine grid resolution to resolve thin substructures such as jets and wall boundaries, resulting in a long simulation time. For mixing in stably stratified large enclosures, the BMIX++ code (Berkeley mechanistic MIXing code in C++) has been developed to implement a highly efficient analysis method for stratification where the ambient fluid volume is represented by one-dimensional (1-D) transient partial differential equations and substructures (such as free or wall jets) are modeled with 1-D integral models. This allows very large reductions in computational effort compared to multi-dimensional CFD modeling. One heat-up experiment performed at the Finland POOLEX facility, which was designed to study phenomena relevant to Nordic design BWR suppression pool including thermal stratification and mixing, is used for validation. Comparisons between the BMIX++, GOTHIC, and CFD calculations against the POOLEX experimental data are discussed in detail.

Haihua Zhao; Ling Zou; Hongbin Zhang

2014-01-01T23:59:59.000Z

252

Audit Report on "Depleted Uranium Hexafluoride Conversion," DOE...  

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

Marketing Administration Other Agencies You are here Home Audit Report on "Depleted Uranium Hexafluoride Conversion," DOEIG-0642 Audit Report on "Depleted Uranium Hexafluoride...

253

Follow-up of Depleted Uranium Hexafluoride Conversion, IG-0751...  

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

Marketing Administration Other Agencies You are here Home Follow-up of Depleted Uranium Hexafluoride Conversion, IG-0751 Follow-up of Depleted Uranium Hexafluoride...

254

Depleted Uranium Operations at the Y-12 National Security Complex...  

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

Sites Power Marketing Administration Other Agencies You are here Home Depleted Uranium Operations at the Y-12 National Security Complex, G-0570 Depleted Uranium Operations...

255

Depleted UF6 Production and Handling Slide Presentation  

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

Production and Handling Depleted UF6 Production and Handling Slide Presentation An online slide presentation about production and handling of depleted UF6, from mining of uranium...

256

FAQ 14-What does a depleted uranium hexafluoride cylinder look...  

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

depleted uranium hexafluoride cylinder look like? What does a depleted uranium hexafluoride cylinder look like? A picture is worth a thousand words The pictures below show typical...

257

California Working Natural Gas Underground Storage Depleted Fields...  

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

Natural Gas Underground Storage Depleted Fields Capacity (Million Cubic Feet) California Working Natural Gas Underground Storage Depleted Fields Capacity (Million Cubic...

258

EIA - Natural Gas Pipeline Network - Depleted Reservoir Storage...  

Annual Energy Outlook 2012 (EIA)

Depleted Reservoir Storage Configuration About U.S. Natural Gas Pipelines - Transporting Natural Gas based on data through 20072008 with selected updates Depleted Production...

259

Production and Handling Slide 42: Typical Depleted Cylinder Storage...  

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

Typical Depleted Cylinder Storage Yard Skip Presentation Navigation First Slide Previous Slide Next Slide Last Presentation Table of Contents Typical Depleted Cylinder Storage Yard...

260

Maryland Natural Gas Underground Storage Depleted Fields Capacity...  

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

Underground Storage Depleted Fields Capacity (Million Cubic Feet) Maryland Natural Gas Underground Storage Depleted Fields Capacity (Million Cubic Feet) Decade Year-0 Year-1 Year-2...

Note: This page contains sample records for the topic "thermal depletion model" 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

Tennessee Natural Gas Underground Storage Depleted Fields Capacity...  

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

Underground Storage Depleted Fields Capacity (Million Cubic Feet) Tennessee Natural Gas Underground Storage Depleted Fields Capacity (Million Cubic Feet) Decade Year-0 Year-1...

262

Nebraska Natural Gas Underground Storage Depleted Fields Capacity...  

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

Underground Storage Depleted Fields Capacity (Million Cubic Feet) Nebraska Natural Gas Underground Storage Depleted Fields Capacity (Million Cubic Feet) Decade Year-0 Year-1 Year-2...

263

Arkansas Natural Gas Underground Storage Depleted Fields Capacity...  

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

Underground Storage Depleted Fields Capacity (Million Cubic Feet) Arkansas Natural Gas Underground Storage Depleted Fields Capacity (Million Cubic Feet) Decade Year-0 Year-1 Year-2...

264

Colorado Natural Gas Underground Storage Depleted Fields Capacity...  

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

Underground Storage Depleted Fields Capacity (Million Cubic Feet) Colorado Natural Gas Underground Storage Depleted Fields Capacity (Million Cubic Feet) Decade Year-0 Year-1 Year-2...

265

Oklahoma Natural Gas Underground Storage Depleted Fields Capacity...  

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

Underground Storage Depleted Fields Capacity (Million Cubic Feet) Oklahoma Natural Gas Underground Storage Depleted Fields Capacity (Million Cubic Feet) Decade Year-0 Year-1 Year-2...

266

Oregon Natural Gas Underground Storage Depleted Fields Capacity...  

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

Underground Storage Depleted Fields Capacity (Million Cubic Feet) Oregon Natural Gas Underground Storage Depleted Fields Capacity (Million Cubic Feet) Decade Year-0 Year-1 Year-2...

267

Ohio Natural Gas Underground Storage Depleted Fields Capacity...  

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

Underground Storage Depleted Fields Capacity (Million Cubic Feet) Ohio Natural Gas Underground Storage Depleted Fields Capacity (Million Cubic Feet) Decade Year-0 Year-1 Year-2...

268

Montana Natural Gas Underground Storage Depleted Fields Capacity...  

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

Underground Storage Depleted Fields Capacity (Million Cubic Feet) Montana Natural Gas Underground Storage Depleted Fields Capacity (Million Cubic Feet) Decade Year-0 Year-1 Year-2...

269

New Mexico Working Natural Gas Underground Storage Depleted Fields...  

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

Natural Gas Underground Storage Depleted Fields Capacity (Million Cubic Feet) New Mexico Working Natural Gas Underground Storage Depleted Fields Capacity (Million Cubic Feet)...

270

Thermally driven escape from Pluto's atmosphere: A combined fluid/kinetic model  

E-Print Network (OSTI)

A combined fluid/kinetic model is developed to calculate thermally driven escape of N2 from Pluto's atmosphere for two solar heating conditions: no heating above 1450 km and solar minimum heating conditions. In the combined model, one-dimensional fluid equations are applied for the dense part of the atmosphere, while the exobase region is described by a kinetic model and calculated by the direct simulation Monte Carlo method. Fluid and kinetic parts of the model are iteratively solved in order to maintain constant total mass and energy fluxes through the simulation region. Although the atmosphere was found to be highly extended, with an exobase altitude at ~6000 km at solar minimum, the outflow remained subsonic and the escape rate was within a factor of two of the Jeans rate for the exobase temperatures determined. This picture is drastically different from recent predictions obtained solely using a fluid model which, in itself, requires assumptions about atmospheric density, flow velocity and energy flux ca...

Tucker, O J; Deighan, J I; Volkov, A N; Johnson, R E

2011-01-01T23:59:59.000Z

271

Modeling Simulation Of Pyrolysis Of Biomass: Effect Of Thermal Conductivity, Reactor Temperature And Particle Size On Product Concentrations  

E-Print Network (OSTI)

The simultaneous chemical kinetics and heat transfer model is used to predict the effects of the most important physical and thermal properties (thermal conductivity, reactor temperature and particle size) of the feedstock on the convective-radiant pyrolysis of biomass fuels. The effects of these parameters have been analyzed for different geometries such as slab, cylinder and sphere. Finite difference method is employed for solving heat transfer model equation while Runge-Kutta 4 th order method is used for solving chemical kinetics model equations. Simulations are carried out for equivalent radius ranging from 0.0000125 m to 0.02 m, and temperature ranging from 303 K to 2100 K.

Chaurasia And Babu; A. S. Chaurasia; B. V. Babu

2003-01-01T23:59:59.000Z

272

Developing a Cost Model and Methodology to Estimate Capital Costs for Thermal Energy Storage  

DOE Green Energy (OSTI)

This report provides an update on the previous cost model for thermal energy storage (TES) systems. The update allows NREL to estimate the costs of such systems that are compatible with the higher operating temperatures associated with advanced power cycles. The goal of the Department of Energy (DOE) Solar Energy Technology Program is to develop solar technologies that can make a significant contribution to the United States domestic energy supply. The recent DOE SunShot Initiative sets a very aggressive cost goal to reach a Levelized Cost of Energy (LCOE) of 6 cents/kWh by 2020 with no incentives or credits for all solar-to-electricity technologies.1 As this goal is reached, the share of utility power generation that is provided by renewable energy sources is expected to increase dramatically. Because Concentrating Solar Power (CSP) is currently the only renewable technology that is capable of integrating cost-effective energy storage, it is positioned to play a key role in providing renewable, dispatchable power to utilities as the share of power generation from renewable sources increases. Because of this role, future CSP plants will likely have as much as 15 hours of Thermal Energy Storage (TES) included in their design and operation. As such, the cost and performance of the TES system is critical to meeting the SunShot goal for solar technologies. The cost of electricity from a CSP plant depends strongly on its overall efficiency, which is a product of two components - the collection and conversion efficiencies. The collection efficiency determines the portion of incident solar energy that is captured as high-temperature thermal energy. The conversion efficiency determines the portion of thermal energy that is converted to electricity. The operating temperature at which the overall efficiency reaches its maximum depends on many factors, including material properties of the CSP plant components. Increasing the operating temperature of the power generation system leads to higher thermal-to-electric conversion efficiency. However, in a CSP system, higher operating temperature also leads to greater thermal losses. These two effects combine to give an optimal system-level operating temperature that may be less than the upper operating temperature limit of system components. The overall efficiency may be improved by developing materials, power cycles, and system-integration strategies that enable operation at elevated temperature while limiting thermal losses. This is particularly true for the TES system and its components. Meeting the SunShot cost target will require cost and performance improvements in all systems and components within a CSP plant. Solar collector field hardware will need to decrease significantly in cost with no loss in performance and possibly with performance improvements. As higher temperatures are considered for the power block, new working fluids, heat-transfer fluids (HTFs), and storage fluids will all need to be identified to meet these new operating conditions. Figure 1 shows thermodynamic conversion efficiency as a function of temperature for the ideal Carnot cycle and 75% Carnot, which is considered to be the practical efficiency attainable by current power cycles. Current conversion efficiencies for the parabolic trough steam cycle, power tower steam cycle, parabolic dish/Stirling, Ericsson, and air-Brayton/steam Rankine combined cycles are shown at their corresponding operating temperatures. Efficiencies for supercritical steam and carbon dioxide (CO{sub 2}) are also shown for their operating temperature ranges.

Glatzmaier, G.

2011-12-01T23:59:59.000Z

273

Dual Bosonic Thermal Green Function and Fermion Correlators of the Massive Thirring Model at a Finite Temperature  

E-Print Network (OSTI)

The Euclidian thermal Green function of the two-dimensional (2D) free massless scalar field in coordinate space is written as the real part of a complex analytic function of a variable that conformally maps the infinite strip $-\\inftyGreen function as the imaginary part of that function. Using both the thermal Green function and its dual, we obtain an explicit series expression for the fermionic correlation functions of the massive Thirring model (MTM) at a finite temperature.

Leonardo Mondaini; E. C. Marino

2007-08-07T23:59:59.000Z

274

Thermal Modeling of NUHOMS HSM-15 and HSM-1 Storage Modules at Calvert Cliffs Nuclear Power Station ISFSI  

Science Conference Proceedings (OSTI)

As part of the Used Fuel Disposition Campaign of the Department of Energy (DOE), visual inspections and temperature measurements were performed on two storage modules in the Calvert Cliffs Nuclear Power Station’s Independent Spent Fuel Storage Installation (ISFSI). Detailed thermal models models were developed to obtain realistic temperature predictions for actual storage systems, in contrast to conservative and bounding design basis calculations.

Suffield, Sarah R.; Fort, James A.; Adkins, Harold E.; Cuta, Judith M.; Collins, Brian A.; Siciliano, Edward R.

2012-10-01T23:59:59.000Z

275

Modeling and simulation of the thermal and psychrometric transient response of all electric ships, internal compartments and cabinets  

Science Conference Proceedings (OSTI)

This paper introduces a general computational model for all electric ships and internal compartments (open and closed domains) that contain heat sources and sinks. A simplified physical model, which combines principles of classical thermodynamics and ... Keywords: relative humidity distribution, temperature distribution, thermal management

J. V. C. Vargas; J. C. Ordonez; R. Hovsapian

2007-07-01T23:59:59.000Z

276

Modeling and Simulation of the Thermal and Psychrometric Transient Response of All-Electric Ships, Internal Compartments and Cabinets  

Science Conference Proceedings (OSTI)

We introduce a general computational model for all-electric ships and internal compartments (open and closed domains) that contain heat sources and sinks. A simplified physical model, which combines principles of classical thermodynamics and heat transfer, ... Keywords: Thermal management, relative humidity distribution, temperature distribution

J.C. Ordonez; J.V.C. Vargas; R. Hovsapian

2008-08-01T23:59:59.000Z

277

ENTHALPY-BASED THERMAL EVOLUTION OF LOOPS. II. IMPROVEMENTS TO THE MODEL  

Science Conference Proceedings (OSTI)

This paper develops the zero-dimensional (0D) hydrodynamic coronal loop model 'Enthalpy-based Thermal Evolution of Loops' (EBTEL) proposed by Klimchuk et al., which studies the plasma response to evolving coronal heating, especially impulsive heating events. The basis of EBTEL is the modeling of mass exchange between the corona and transition region (TR) and chromosphere in response to heating variations, with the key parameter being the ratio of the TR to coronal radiation. We develop new models for this parameter that now include gravitational stratification and a physically motivated approach to radiative cooling. A number of examples are presented, including nanoflares in short and long loops, and a small flare. The new features in EBTEL are important for accurate tracking of, in particular, the density. The 0D results are compared to a 1D hydro code (Hydrad) with generally good agreement. EBTEL is suitable for general use as a tool for (1) quick-look results of loop evolution in response to a given heating function, (2) extensive parameter surveys, and (3) situations where the modeling of hundreds or thousands of elemental loops is needed. A single run takes a few seconds on a contemporary laptop.

Cargill, P. J. [Space and Atmospheric Physics, The Blackett Laboratory, Imperial College, London SW7 2BW (United Kingdom); Bradshaw, S. J. [Department of Physics and Astronomy, Rice University, Houston, TX 77005 (United States); Klimchuk, J. A., E-mail: p.cargill@imperial.ac.uk [NASA Goddard Space Flight Center, Solar Physics Laboratory, Code 671, Greenbelt, MD 20771 (United States)

2012-06-20T23:59:59.000Z

278

A Combined Neutronic-Thermal Hydraulic Model of CERMET NTR Reactor  

Science Conference Proceedings (OSTI)

Abstract. Two different CERMET fueled Nuclear Thermal Propulsion reactors were modeled to determine the optimum coolant channel surface area to volume ratio required to cool a 25,000 lbf rocket engine operating at a specific impulse of 940 seconds. Both reactor concepts were computationally fueled with hexagonal cross section fuel elements having a flat-to-flat distance of 3.51 cm and containing 60 vol.% UO2 enriched to 93wt.%U235 and 40 vol.% tungsten. Coolant channel configuration consisted of a 37 coolant channel fuel element and a 61 coolant channel model representing 0.3 and 0.6 surface area to volume ratios respectively. The energy deposition from decelerating fission products and scattered neutrons and photons was determined using the MCNP monte carlo code and then imported into the STAR-CCM+ computational fluid dynamics code. The 37 coolant channel case was shown to be insufficient in cooling the core to a peak temperature of 3000 K; however, the 61 coolant channel model shows promise for maintaining a peak core temperature of 3000 K, with no more refinements to the surface area to volume ratio. The core was modeled to have a power density of 9.34 GW/m3 with a thrust to weight ratio of 5.7.

Jonathan A. Webb; Brian Gross; William T. Taitano

2011-02-01T23:59:59.000Z

279

Thermal modeling of tanks 241-AW-101 and 241-AN-104 with the TEMPEST code  

SciTech Connect

The TEMPEST code was exercised in a preliminary study of double-shell Tanks 241 -AW-101 and 241-AN-104 thermal behavior. The two-dimensional model used is derived from our earlier studies on heat transfer from Tank 241-SY-101. Several changes were made to the model to simulate the waste and conditions in 241-AW-101 and 241-AN-104. The nonconvective waste layer was assumed to be 254 cm (100 in.) thick for Tank 241-AW-101, and 381 cm (150 in.) in Tank 241-AN-104. The remaining waste was assumed, for each tank, to consist of a convective layer with a 7.6-cm (3-inch) crust on top. The waste heat loads for 241-AW-101 and 241-AN-104 were taken to be 10 kW (3.4E4 Btu/hr) and 12 kW (4.0E4 Btu/hr), respectively. Present model predictions of maximum and convecting waste temperatures are within 1.7{degrees}C (3{degrees}F) of those measured in Tanks 241-AW-101 and 241-AN-104. The difference between the predicted and measured temperature is comparable to the uncertainty of the measurement equipment. These models, therefore, are suitable for estimating the temperatures within the tanks in the event of changing air flows, waste levels, and/or waste configurations.

Antoniak, Z.I.; Recknagle, K.P.

1995-07-01T23:59:59.000Z

280

Coal thermolysis modeling: The effects of restricted diffusion on thermal reaction pathways  

Science Conference Proceedings (OSTI)

The technique of model compound immobilization by covalent surface attachment is being employed to investigate the potential impact of restricted diffusional mobility on the thermal reactivity of coal. This restricted mobility may be imposed in coal as a consequence of its cross-linked, macromolecular structure. A detailed study of the thermolysis of surface-immobilized bibenzyl showed that the rate of unimolecular C-C homolysis is similar to that in fluid phases. Recent studies have foucused on the thermally induced, free radical chain decomposition reactions for surface-immobilized 1,3-diphenylpropane and 1,4-diphenylbutane. For 1,4-diphenylbutane both the reaction rate and product composition are strongly dependent on surface coverage and, hence, the proximity of 1.4-diphenylbutane molecules and hydrogen abstracting radicals on the surface. The rates and selectivities of these key bimolecular reaction steps on the surface might also be affected by the structure of neighboring molecules. In the current study, we are beginning to probe this feature by examining the influence of the structure of co-attached aromatic molecules such as biphenyl and diphenylmethane on the reaction rate and regioselectivity in the thermolysis of 1,4-diphenylbutane. 7 refs. , 1 fig., 2 tabs.

Buchanan, A.C. III; Britt, P.F.; Biggs, C.A.

1989-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "thermal depletion model" 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

Modeling thermal-hydrological response of the unsaturated zone at Yucca Mountain, Nevada, to thermal load at a potential repository  

E-Print Network (OSTI)

Repository at Yucca Mountain. In Materials Research Societystudies using the Yucca Mountain unsaturated zone model.Unsaturated Zone, Yucca Mountain, Nevada. Water Resources

Haukwa, C.B.; Wu, Yu-Shu; Bodvarsson, G.S.

2002-01-01T23:59:59.000Z

282

A STUDY OF ATES THERMAL BEHAVIOR USING A STEADY FLOW MODEL  

E-Print Network (OSTI)

thermal conductivity, Aau heat capacity per unit volume, Ca,thermal conductivity Ac and heat capacity per unit volumeCc• Cw• The heat capacity per unit volume of water is All

Doughty, Christine

2013-01-01T23:59:59.000Z

283

Thermal Modeling and Device Noise Properties of Three-Dimensional-SOI Technology  

E-Print Network (OSTI)

Thermal test structures and ring oscillators (ROs) are fabricated in 0.18-mum three-dimensional (3-D)-SOI technology. Measurements and electrothermal simulations show that thermal and parasitic effects due to 3-D packaging ...

Chen, Tze Wee

284

Transient heat transfer through walls and thermal bridges. numerical modelling: methodology and validation  

Science Conference Proceedings (OSTI)

The current advanced numerical codes for the energy audits carry out 0-dimensional simulation (i.e., one computational node representing the thermal zone), underestimating the effects of thermal bridges on the seasonal heating demand of buildings. The ...

Fabrizio Ascione; Filippo de' Rossi; Nicola Bianco; Giuseppe Peter Vanoli

2012-12-01T23:59:59.000Z

285

Depleted Uranium (DU) Cermet Waste Package  

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

Package Package Depleted Uranium (DU) Cermet Waste Package The steel components of the waste package could be replaced with a uranium cermet. The cermet contains uranium dioxide particulates, which are embedded in steel. Cermets are made with outer layers of clean steel; thus, there is no radiation-contamination hazard in handling the waste packages. Because cermets are made of the same materials that would normally be found in the YM repository (uranium dioxide and steel), there are no chemical compatibility issues. From half to all of the DU inventory in the United States could be used for this application. Depleted Uranium Dioxide Steel Cermet Cross Section of a Depleted Uranium Dioxide Steel Cermet Follow the link below for more information on Cermets:

286

Simulated evolution of fractures and fracture networks subject to thermal cooling: A coupled discrete element and heat conduction model  

SciTech Connect

Advancement of EGS requires improved prediction of fracture development and growth during reservoir stimulation and long-term operation. This, in turn, requires better understanding of the dynamics of the strongly coupled thermo-hydro-mechanical (THM) processes within fractured rocks. We have developed a physically based rock deformation and fracture propagation simulator by using a quasi-static discrete element model (DEM) to model mechanical rock deformation and fracture propagation induced by thermal stress and fluid pressure changes. We also developed a network model to simulate fluid flow and heat transport in both fractures and porous rock. In this paper, we describe results of simulations in which the DEM model and network flow & heat transport model are coupled together to provide realistic simulation of the changes of apertures and permeability of fractures and fracture networks induced by thermal cooling and fluid pressure changes within fractures. Various processes, such as Stokes flow in low velocity pores, convection-dominated heat transport in fractures, heat exchange between fluid-filled fractures and solid rock, heat conduction through low-permeability matrices and associated mechanical deformations are all incorporated into the coupled model. The effects of confining stresses, developing thermal stress and injection pressure on the permeability evolution of fracture and fracture networks are systematically investigated. Results are summarized in terms of implications for the development and evolution of fracture distribution during hydrofracturing and thermal stimulation for EGS.

Huang, Hai; Plummer, Mitchell; Podgorney, Robert

2013-02-01T23:59:59.000Z

287

Electrical and thermal finite element modeling of arc faults in photovoltaic bypass diodes.  

DOE Green Energy (OSTI)

Arc faults in photovoltaic (PV) modules have caused multiple rooftop fires. The arc generates a high-temperature plasma that ignites surrounding materials and subsequently spreads the fire to the building structure. While there are many possible locations in PV systems and PV modules where arcs could initiate, bypass diodes have been suspected of triggering arc faults in some modules. In order to understand the electrical and thermal phenomena associated with these events, a finite element model of a busbar and diode was created. Thermoelectrical simulations found Joule and internal diode heating from normal operation would not normally cause bypass diode or solder failures. However, if corrosion increased the contact resistance in the solder connection between the busbar and the diode leads, enough voltage potentially would be established to arc across micron-scale electrode gaps. Lastly, an analytical arc radiation model based on observed data was employed to predicted polymer ignition times. The model predicted polymer materials in the adjacent area of the diode and junction box ignite in less than 0.1 seconds.

Bower, Ward Isaac; Quintana, Michael A.; Johnson, Jay

2012-01-01T23:59:59.000Z

288

Modelling Concentrating Solar Power with Thermal Energy Storage for Integration Studies (Presentation)  

SciTech Connect

Concentrating solar power with thermal energy storage (CSP-TES) can provide multiple benefits to the grid, including low marginal cost energy and the ability to levelize load, provide operating reserves, and provide firm capacity. It is challenging to properly value the integration of CSP because of the complicated nature of this technology. Unlike completely dispatchable fossil sources, CSP is a limited energy resource, depending on the hourly and daily supply of solar energy. To optimize the use of this limited energy, CSP-TES must be implemented in a production cost model with multiple decision variables for the operation of the CSP-TES plant. We develop and implement a CSP-TES plant in a production cost model that accurately characterizes the three main components of the plant: solar field, storage tank, and power block. We show the effect of various modelling simplifications on the value of CSP, including: scheduled versus optimized dispatch from the storage tank and energy-only operation versus co-optimization with ancillary services.

Hummon, M.; Jorgenson, J.; Denholm, P.; Mehos, M.

2013-10-01T23:59:59.000Z

289

Modelling Concentrating Solar Power with Thermal Energy Storage for Integration Studies: Preprint  

SciTech Connect

Concentrating solar power with thermal energy storage (CSP-TES) can provide multiple benefits to the grid, including low marginal cost energy and the ability to levelize load, provide operating reserves, and provide firm capacity. It is challenging to properly value the integration of CSP because of the complicated nature of this technology. Unlike completely dispatchable fossil sources, CSP is a limited energy resource, depending on the hourly and daily supply of solar energy. To optimize the use of this limited energy, CSP-TES must be implemented in a production cost model with multiple decision variables for the operation of the CSP-TES plant. We develop and implement a CSP-TES plant in a production cost model that accurately characterizes the three main components of the plant: solar field, storage tank, and power block. We show the effect of various modelling simplifications on the value of CSP, including: scheduled versus optimized dispatch from the storage tank and energy-only operation versus co-optimization with ancillary services.

Hummon, M.; Denholm, P.; Jorgenson, J.; Mehos, M.

2013-10-01T23:59:59.000Z

290

Thermal shock modeling of Ultra-High Temperature Ceramics under active cooling  

Science Conference Proceedings (OSTI)

Thermal shock resistance is one of the most important parameters in Ultra-High Temperature Ceramics (UHTCs) since it determines their performance in various applications. In this paper, due to the fact that the material parameters of UHTCs are very sensitive ... Keywords: Active cooling, Target temperature, Thermal protection system, Thermal shock resistance, Ultra-High Temperature Ceramics

Weiguo Li; Fan Yang; Daining Fang

2009-12-01T23:59:59.000Z

291

A steady state thermal duct model derived by fin-theory approach and applied on an unglazed solar collector  

SciTech Connect

This paper presents the thermal modelling of an unglazed solar collector (USC) flat panel, with the aim of producing a detailed yet swift thermal steady-state model. The model is analytical, one-dimensional (1D) and derived by a fin-theory approach. It represents the thermal performance of an arbitrary duct with applied boundary conditions equal to those of a flat panel collector. The derived model is meant to be used for efficient optimisation and design of USC flat panels (or similar applications), as well as detailed thermal analysis of temperature fields and heat transfer distributions/variations at steady-state conditions; without requiring a large amount of computational power and time. Detailed surface temperatures are necessary features for durability studies of the surface coating, hence the effect of coating degradation on USC and system performance. The model accuracy and proficiency has been benchmarked against a detailed three-dimensional Finite Difference Model (3D FDM) and two simpler 1D analytical models. Results from the benchmarking test show that the fin-theory model has excellent capabilities of calculating energy performances and fluid temperature profiles, as well as detailed material temperature fields and heat transfer distributions/variations (at steady-state conditions), while still being suitable for component analysis in junction to system simulations as the model is analytical. The accuracy of the model is high in comparison to the 3D FDM (the prime benchmark), as long as the fin-theory assumption prevails (no 'or negligible' temperature gradient in the fin perpendicularly to the fin length). Comparison with the other models also shows that when the USC duct material has a high thermal conductivity, the cross-sectional material temperature adopts an isothermal state (for the assessed USC duct geometry), which makes the 1D isothermal model valid. When the USC duct material has a low thermal conductivity, the heat transfer course of events adopts a 1D heat flow that reassembles the conditions of the 1D simple model (for the assessed USC duct geometry); 1D heat flow through the top and bottom fins/sheets as the duct wall reassembles a state of adiabatic condition. (author)

Stojanovic, B.; Hallberg, D.; Akander, J. [Building Materials Technology, KTH Research School, Centre for Built Environment, University of Gaevle, SE-801 76 Gaevle (Sweden)

2010-10-15T23:59:59.000Z

292

Thermal History of the Felsite Unit, Geysers Geothermal Field, From Thermal Modeling of 40Ar/39Ar Incremental Heating Data  

DOE Green Energy (OSTI)

An Ar-40/Ar-39 and U-Pb study was performed of the Geysers plutonic complex of the Geysers Geothermal Field in California. Sixty-nine ion microprobe spot analyses of zircons from four granite samples from the plutonic complex that underlies the Geysers geothermal field yielded Pb-207/Pb-206 vs. U-238/Pb-206 concordia ages ranging from 1.13 {+-} 0.04 Ma to 1.25 {+-} 0.04 Ma. The U-Pb ages coincide closely with Ar-40/Ar-39 age spectrum plateau and ''terminal'' ages from coexisting K-feldspars and with the eruption ages of overlying volcanic rocks. The data indicate that the granite crystallized at 1.18 Ma and had cooled below 350 C by {approximately}0.9-1.0 Ma. Interpretation of the feldspar Ar-40/Ar-39 age data using multi-diffusion domain theory indicates that post-emplacement rapid cooling was succeeded either by slower cooling from 350-300 C between 1.0 and 0.4 Ma or transitory reheating to 300-350 C at about 0.4-0.6 Ma. Heat flow calculations constrained with K-feldspar thermal histories and the pre sent elevated regional heal flow anomaly demonstrate that appreciable heat input from sources external to the known Geysers plutonic complex is required to maintain the geothermal system. This requirement is satisfied by either a large, underlying, convecting magma chamber (now solidified) emplaced at 1.2 Ma or episodic intrusion of smaller bodies from 1.2-0.6 Ma.

T. M. Harrison (U of California); G. B. Dalrymple (Oregon State U); J. B. Hulen (U of Utah); M. A. Lanphere; M. Grove; O. M. Lovera

1999-08-19T23:59:59.000Z

293

Nuclear conflict and ozone depletion Quick summary  

E-Print Network (OSTI)

Nuclear conflict and ozone depletion Quick summary o Regional nuclear war could cause global which traps pollutants o Nuclear weapons cause explosions, which then causes things around the vicinity to start burning, which in turn releases black carbon; it is not the nuclear material or fallout causing

Toohey, Darin W.

294

Stratospheric Ozone Depletion: The Main Driver of Twentieth-Century Atmospheric Circulation Changes in the Southern Hemisphere  

Science Conference Proceedings (OSTI)

The importance of stratospheric ozone depletion on the atmospheric circulation of the troposphere is studied with an atmospheric general circulation model, the Community Atmospheric Model, version 3 (CAM3), for the second half of the twentieth ...

Lorenzo M. Polvani; Darryn W. Waugh; Gustavo J. P. Correa; Seok-Woo Son

2011-02-01T23:59:59.000Z

295

Modeling, design and thermal performance of a BIPV/T system thermally coupled with a ventilated concrete slab in a low energy solar house: Part 2, ventilated concrete slab  

Science Conference Proceedings (OSTI)

This paper is the second of two papers that describe the modeling and design of a building-integrated photovoltaic-thermal (BIPV/T) system thermally coupled with a ventilated concrete slab (VCS) adopted in a prefabricated, two-storey detached, low energy solar house and their performance assessment based on monitored data. The VCS concept is based on an integrated thermal-structural design with active storage of solar thermal energy while serving as a structural component - the basement floor slab ({proportional_to}33 m{sup 2}). This paper describes the numerical modeling, design, and thermal performance assessment of the VCS. The thermal performance of the VCS during the commissioning of the unoccupied house is presented. Analysis of the monitored data shows that the VCS can store 9-12 kWh of heat from the total thermal energy collected by the BIPV/T system, on a typical clear sunny day with an outdoor temperature of about 0 C. It can also accumulate thermal energy during a series of clear sunny days without overheating the slab surface or the living space. This research shows that coupling the VCS with the BIPV/T system is a viable method to enhance the utilization of collected solar thermal energy. A method is presented for creating a simplified three-dimensional, control volume finite difference, explicit thermal model of the VCS. The model is created and validated using monitored data. The modeling method is suitable for detailed parametric study of the thermal behavior of the VCS without excessive computational effort. (author)

Chen, Yuxiang; Galal, Khaled; Athienitis, A.K. [Dept. of Building, Civil and Environmental Engineering, Concordia University, 1455 De Maisonneuve West, EV6.139, Montreal, Quebec (Canada)

2010-11-15T23:59:59.000Z

296

Thermal-Hydraulic Modeling of the Primary Coolant System of Light Water Reactors During Severely Degraded Core Accidents  

Science Conference Proceedings (OSTI)

The transport of fission-product vapors and aerosols that would be released from an LWR primary system in postulated severe accidents depends on the prevalent thermal-hydraulic conditions. The analytic models developed in this study are incorporated in the PSAAC modular computer program, which can help predict more realistic estimates of accident consequences.

1984-07-01T23:59:59.000Z

297

Climate Response at the Paleocene–Eocene Thermal Maximum to Greenhouse Gas Forcing—A Model Study with CCSM3  

Science Conference Proceedings (OSTI)

The Paleocene–Eocene Thermal Maximum (PETM; 55 Ma) is of particular interest since it is regarded as a suitable analog to future climate change. In this study, the PETM climate is investigated using the Community Climate System Model (CCSM3) with ...

A. Winguth; C. Shellito; C. Shields; C. Winguth

2010-05-01T23:59:59.000Z

298

Investigation of the Thermal Stability of Irradiation and Cold Work Defects in Zirconium-based Model Alloys: 2011 Progress Report  

Science Conference Proceedings (OSTI)

This report covers the work performed in 2011 on the thermal stability of irradiation and strain hardening defects in several zirconium-based model alloys with low niobium content. The work involves various tests and measurements on tubular or plate specimens irradiated in the Russian BOR-60 reactor.

2012-06-06T23:59:59.000Z

299

Investigation of the Thermal Stability of Irradiation and Cold Work Defects in Zirconium-based Model Alloys  

Science Conference Proceedings (OSTI)

This report covers the work performed in 2010 on the thermal stability of irradiation and strain hardening defects in zirconium-based model alloys with low niobium content. The work involves various tests and measurements on tubular or plate specimens irradiated in the Russian BOR-60 reactor.

2011-07-13T23:59:59.000Z

300

Investigation of the Thermal Stability of Irradiation and Cold Work Defects in Zirconium-based Model Alloys  

Science Conference Proceedings (OSTI)

This report describes the work performed in 2009 on the thermal stability of irradiation and strain hardening defects in zirconium-based model alloys with low niobium content. The work involves various tests and measurements on tubular or plate specimens irradiated in the Russian BOR-60 reactor.

2010-05-17T23:59:59.000Z

Note: This page contains sample records for the topic "thermal depletion model" 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

Thermal performance evaluation of the Northrup Model NSC-01-0732 concentrating solar collector array at outdoor conditions  

DOE Green Energy (OSTI)

The thermal performance tests conducted on the Northrup Model NSC-01-0732 concentrating, tracking solar collector for approximately two months (from the end of August to the first part of October 1979) are described. These tests were made using the Marshall Space Flight Center's Solar House Test Facility.

Not Available

1979-12-01T23:59:59.000Z

302

ELSEVIER Journal of Nuclear Materials 244 (1997) 85-100 RACLETTE: a model for evaluating the thermal response of plasma  

E-Print Network (OSTI)

ELSEVIER Journal of Nuclear Materials 244 (1997) 85-100 RACLETTE: a model for evaluating the thermal response of plasma facing components to slow high power plasma transients. Part I: Theory, in the current engineering design phase of the International Ther- monuclear Experimental Reactor (ITER

Raffray, A. René

303

Thermal mass performance in residential construction : an energy analysis using a cube model; Energy analysis using a cube model.  

E-Print Network (OSTI)

??Given the pervasiveness of energy efficiency concerns in the built environment, this research aims to answer key questions regarding the performance of thermal mass construction.… (more)

Ledwith, Alison C. (Alison Catherine)

2012-01-01T23:59:59.000Z

304

Improving Thermal Model Prediction Through Statistical Analysis of Irradiation and Post-Irradiation Data from AGR Experiments  

SciTech Connect

As part of the Research and Development program for Next Generation High Temperature Reactors (HTR), a series of irradiation tests, designated as Advanced Gas-cooled Reactor (AGR), have been defined to support development and qualification of fuel design, fabrication process, and fuel performance under normal operation and accident conditions. The AGR tests employ fuel compacts placed in a graphite cylinder shrouded by a steel capsule and instrumented with thermocouples (TC) embedded in graphite blocks enabling temperature control. The data representing the crucial test fuel conditions (e.g., temperature, neutron fast fluence, and burnup) while impossible to obtain from direct measurements are calculated by physics and thermal models. The irradiation and post-irradiation examination (PIE) experimental data are used in model calibration effort to reduce the inherent uncertainty of simulation results. This paper is focused on fuel temperature predicted by the ABAQUS code’s finite element-based thermal models. The work follows up on a previous study, in which several statistical analysis methods were adapted, implemented in the NGNP Data Management and Analysis System (NDMAS), and applied for improving qualification of AGR-1 thermocouple data. The present work exercises the idea that the abnormal trends of measured data observed from statistical analysis may be caused by either measuring instrument deterioration or physical mechanisms in capsules that may have shifted the system thermal response. As an example, the uneven reduction of the control gas gap in Capsule 5 revealed by the capsule metrology measurements in PIE helps justify the reduction in TC readings instead of TC drift. This in turn prompts modification of thermal model to better fit with experimental data, thus help increase confidence, and in other word reduce model uncertainties in thermal simulation results of the AGR-1 test.

Dr. Binh T. Pham; Grant L. Hawkes; Jeffrey J. Einerson

2012-10-01T23:59:59.000Z

305

THERMAL MODELING ANALYSIS OF CST MEDIA IN THE SMALL COLUMN ION EXCHANGE PROJECT  

SciTech Connect

Models have been developed to simulate the thermal characteristics of Crystalline Silicotitanate (CST) ion exchange media fully loaded with radioactive cesium in a column configuration and distributed within a waste storage tank. This work was conducted to support the Small Column Ion Exchange (SCIX) program which is focused on processing dissolved, high-sodium salt waste for the removal of specific radionuclides (including Cs-137, Sr-90, and actinides) within a High Level Waste (HLW) storage tank at the Savannah River Site. The SCIX design includes CST columns inserted and supported in the tank top risers for cesium removal. Temperature distributions and maximum temperatures across the column were calculated with a focus on process upset conditions. A two-dimensional computational modeling approach for the in-column ion-exchange domain was taken to include conservative, bounding estimates for key parameters such that the results would provide the maximum centerline temperatures achievable under the design configurations using a feed composition known to promote high cesium loading on CST. One salt processing scenario includes the transport of the loaded (and possibly ground) CST media to the treatment tank floor. Therefore, additional thermal modeling calculations were conducted using a three-dimensional approach to evaluate temperature distributions for the entire in-tank domain including distribution of the spent CST media either as a mound or a flat layer on the tank floor. These calculations included mixtures of CST with HLW sludge or loaded Monosodium Titanate (MST) media used for strontium/actinide sorption. The current full-scale design for the CST column includes one central cooling pipe and four outer cooling tubes. Most calculations assumed that the fluid within the column was stagnant (i.e. no buoyancy-induced flow) for a conservative estimate. A primary objective of these calculations was to estimate temperature distributions across packed CST beds immersed in waste supernate or filled with dry air under various accident scenarios. Accident scenarios evaluated included loss of salt solution flow through the bed (a primary heat transfer mechanism), inadvertent column drainage, and loss of active cooling in the column. The calculation results showed that for a wet CST column with active cooling through one central and four outer tubes and 35 C ambient external air, the peak temperature for the fully-loaded column is about 63 C under the loss of fluid flow accident, which is well below the supernate boiling point. The peak temperature for the naturally-cooled (no active, engineered cooling) wet column is 156 C under fully-loaded conditions, exceeding the 130 C boiling point. Under these conditions, supernate boiling would maintain the column temperature near 130 C until all supernate was vaporized. Without active engineered cooling and assuming a dry column suspended in unventilated air at 35 C, the fully-loaded column is expected to rise to a maximum of about 258 C due to the combined loss-of coolant and column drainage accidents. The modeling results demonstrate that the baseline design using one central and four outer cooling tubes provides a highly efficient cooling mechanism for reducing the maximum column temperature. Results for the in-tank modeling calculations clearly indicate that when realistic heat transfer boundary conditions are imposed on the bottom surface of the tank wall, as much as 450 gallons of ground CST (a volume equivalent to two ion exchange processing cycles) in an ideal hemispherical shape (the most conservative geometry) can be placed in the tank without exceeding the 100 C wall temperature limit. Furthermore, in the case of an evenly-distributed flat layer, the tank wall reaches the temperature limit after the ground CST material reaches a height of approximately 8 inches.

Lee, S.

2010-11-01T23:59:59.000Z

306

Modeling CO2 Sequestration in a Saline Reservoir and Depleted Oil Reservoir to Evaluate The Regional CO2 Sequestration Potential of The Ozark Plateau Aquifer System, South-Central Kansas  

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

CO CO 2 Sequestration in a Saline Reservoir and Depleted Oil Reservoir to Evaluate The Regional CO 2 Sequestration Potential of The Ozark Plateau Aquifer System, South-Central Kansas Background Carbon capture, utilization and storage (CCUS) technologies offer the potential for reducing CO 2 emissions without adversely influencing energy use or hindering economic growth. Deploying these technologies in commercial-scale applications requires adequate geologic formations capable of (1) storing large volumes of CO 2 , (2) receiving injected CO 2 at efficient and economic rates, and (3) retaining CO 2 safely over extended periods. Research efforts are currently focused on conventional and unconventional storage formations within depositional environments such as: deltaic, fluvial, alluvial,

307

Fighting Fire with Fire: Modeling the Datacenter-Scale Effects of Targeted Superlattice Thermal Management  

SciTech Connect

Local thermal hot-spots in microprocessors lead to worst case provisioning of global cooling resources, especially in large-scale systems. However, efficiency of cooling solutions degrade non-linearly with supply temperature, resulting in high power consumption and cost in cooling - 50 {approx} 100% of IT power. Recent advances in active cooling techniques have shown on-chip thermoelectric coolers (TECs) to be very efficient at selectively eliminating small hot-spots, where applying current to a superlattice film deposited between silicon and the heat spreader results in a Peltier effect that spreads the heat and lowers the temperature of the hot-spot significantly to improve chip reliability. In this paper, we propose that hot-spot mitigation using thermoelectric coolers can be used as a power management mechanism to allow global coolers to be provisioned for a better worst case temperature leading to substantial savings in cooling power. In order to quantify the potential power savings from using TECs in data center servers, we present a detailed power model that integrates on-chip dynamic and leakage power sources, heat diffusion through the entire chip, TEC and global cooler efficiencies, and all their mutual interactions. Our multiscale analysis shows that, for a typical data center, TECs allow global coolers to operate at higher temperatures without degrading chip lifetime, and thus save {approx}27% cooling power on average while providing the same processor reliability as a data center running at 288K.

Biswas, S; Tiwari, M; Theogarajan, L; Sherwood, T P; Chong, F T

2010-11-11T23:59:59.000Z

308

A LUMPED-PARAMETER DYNAMIC MODEL OF A THERMAL REGENERATOR FOR FREE-PISTON STIRLING ENGINES  

E-Print Network (OSTI)

Design of a 2.5kW Low Temperature Stirling Engine for Distributed Solar Thermal Generation Mike He on the design of a Stirling engine for distributed solar thermal ap- plications. In particular, we design for experimentation. Stirling engines can have broad significance and technological advantages for distributed

Barth, Eric J.

309

Numerical study of error propagation in Monte Carlo depletion simulations  

Science Conference Proceedings (OSTI)

Improving computer technology and the desire to more accurately model the heterogeneity of the nuclear reactor environment have made the use of Monte Carlo depletion codes more attractive in recent years, and feasible (if not practical) even for 3-D depletion simulation. However, in this case statistical uncertainty is combined with error propagating through the calculation from previous steps. In an effort to understand this error propagation, a numerical study was undertaken to model and track individual fuel pins in four 17 x 17 PWR fuel assemblies. By changing the code's initial random number seed, the data produced by a series of 19 replica runs was used to investigate the true and apparent variance in k{sub eff}, pin powers, and number densities of several isotopes. While this study does not intend to develop a predictive model for error propagation, it is hoped that its results can help to identify some common regularities in the behavior of uncertainty in several key parameters. (authors)

Wyant, T.; Petrovic, B. [Nuclear and Radiological Engineering, Georgia Inst. of Technology, 770 State Street, Atlanta, GA 30332-0745 (United States)

2012-07-01T23:59:59.000Z

310

Depleted Uranium Uses: Regulatory Requirements and Issues  

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

1 Depleted Uranium Uses Depleted Uranium Uses Regulatory Requirements Regulatory Requirements and Issues and Issues Nancy L. Ranek Nancy L. Ranek Argonne National Laboratory Argonne National Laboratory August 5, 1998 August 5, 1998 Beneficial Reuse '98 Beneficial Reuse '98 Knoxville, TN Knoxville, TN NOTES Work Performed for: Office of Facilities (NE-40) Office of Nuclear Energy, Science and Technology U.S. Department of Energy Work Performed by: Environmental Assessment Division Argonne National Laboratory 955 L'Enfant Plaza North, S.W. Washington, D.C. 20024 Phone: 202/488-2417 E-mail: ranekn@smtplink.dis.anl.gov 2 2 2 Programmatic Environmental Programmatic Environmental Impact Statement (PEIS) Impact Statement (PEIS) Draft PEIS Published 12/97 * Preferred Alternative = 100% Use

311

Depleted UF6 Conversion facility EIS Topics  

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

Topics Topics Depleted UF6 Conversion Facility EIS Topics A listing of topics included in the Depleted UF6 Conversion Facility EISs. DOE addressed the following environmental issues when assessing the potential environmental impacts of the alternatives in the two site-specific EISs. DOE solicited comment from the Federal agencies, Native American tribes, state and local governments, and the general public on these and any other issues as part of the public scoping process: Potential impacts on health from DUF6 conversion activities, including potential impacts to workers and the public from exposure to radiation and chemicals during routine and accident conditions for the construction, operation, maintenance, and decontamination and decommissioning of DUF6 conversion facilities.

312

Assessment of Preferred Depleted Uranium Disposal Forms  

SciTech Connect

The Department of Energy (DOE) is in the process of converting about 700,000 metric tons (MT) of depleted uranium hexafluoride (DUF6) containing 475,000 MT of depleted uranium (DU) to a stable form more suitable for long-term storage or disposal. Potential conversion forms include the tetrafluoride (DUF4), oxide (DUO2 or DU3O8), or metal. If worthwhile beneficial uses cannot be found for the DU product form, it will be sent to an appropriate site for disposal. The DU products are considered to be low-level waste (LLW) under both DOE orders and Nuclear Regulatory Commission (NRC) regulations. The objective of this study was to assess the acceptability of the potential DU conversion products at potential LLW disposal sites to provide a basis for DOE decisions on the preferred DU product form and a path forward that will ensure reliable and efficient disposal.

Croff, A.G.; Hightower, J.R.; Lee, D.W.; Michaels, G.E.; Ranek, N.L.; Trabalka, J.R.

2000-06-01T23:59:59.000Z

313

Depleted uranium plasma reduction system study  

Science Conference Proceedings (OSTI)

A system life-cycle cost study was conducted of a preliminary design concept for a plasma reduction process for converting depleted uranium to uranium metal and anhydrous HF. The plasma-based process is expected to offer significant economic and environmental advantages over present technology. Depleted Uranium is currently stored in the form of solid UF{sub 6}, of which approximately 575,000 metric tons is stored at three locations in the U.S. The proposed system is preconceptual in nature, but includes all necessary processing equipment and facilities to perform the process. The study has identified total processing cost of approximately $3.00/kg of UF{sub 6} processed. Based on the results of this study, the development of a laboratory-scale system (1 kg/h throughput of UF6) is warranted. Further scaling of the process to pilot scale will be determined after laboratory testing is complete.

Rekemeyer, P.; Feizollahi, F.; Quapp, W.J.; Brown, B.W.

1994-12-01T23:59:59.000Z

314

Thermal decoupling and the smallest subhalo mass in dark matter models with Sommerfeld-enhanced annihilation rates  

E-Print Network (OSTI)

We consider dark matter consisting of weakly interacting massive particles (WIMPs) and revisit in detail its thermal evolution in the early universe, with a particular focus on models where the annihilation rate is enhanced by the Sommerfeld effect. After chemical decoupling, or freeze-out, dark matter no longer annihilates but is still kept in local thermal equilibrium due to scattering events with the much more abundant standard model particles. During kinetic decoupling, even these processes stop to be effective, which eventually sets the scale for a small-scale cutoff in the matter density fluctuations. Afterwards, the WIMP temperature decreases more quickly than the heat bath temperature, which causes dark matter to reenter an era of annihilation if the cross-section is enhanced by the Sommerfeld effect. Here, we give a detailed and self-consistent description of these effects. As an application, we consider the phenomenology of simple leptophilic models that have been discussed in the literature and fin...

Aarssen, Laura G van den; Goedecke, Yasar C

2012-01-01T23:59:59.000Z

315

The ultimate disposition of depleted uranium  

SciTech Connect

Significant amounts of the depleted uranium (DU) created by past uranium enrichment activities have been sold, disposed of commercially, or utilized by defense programs. In recent years, however, the demand for DU has become quite small compared to quantities available, and within the US Department of Energy (DOE) there is concern for any risks and/or cost liabilities that might be associated with the ever-growing inventory of this material. As a result, Martin Marietta Energy Systems, Inc. (Energy Systems), was asked to review options and to develop a comprehensive plan for inventory management and the ultimate disposition of DU accumulated at the gaseous diffusion plants (GDPs). An Energy Systems task team, under the chairmanship of T. R. Lemons, was formed in late 1989 to provide advice and guidance for this task. This report reviews options and recommends actions and objectives in the management of working inventories of partially depleted feed (PDF) materials and for the ultimate disposition of fully depleted uranium (FDU). Actions that should be considered are as follows. (1) Inspect UF{sub 6} cylinders on a semiannual basis. (2) Upgrade cylinder maintenance and storage yards. (3) Convert FDU to U{sub 3}O{sub 8} for long-term storage or disposal. This will include provisions for partial recovery of costs to offset those associated with DU inventory management and the ultimate disposal of FDU. Another recommendation is to drop the term tails'' in favor of depleted uranium'' or DU'' because the tails'' label implies that it is waste.'' 13 refs.

Not Available

1990-12-01T23:59:59.000Z

316

A coupled THC model of the FEBEX in situ test with bentonite swelling and chemical and thermal osmosis  

SciTech Connect

The performance assessment of a geological repository for radioactive waste requires quantifying the geochemical evolution of the bentonite engineered barrier. This barrier will be exposed to coupled thermal (T), hydrodynamic (H), mechanical (M) and chemical (C) processes. This paper presents a coupled THC model of the FEBEX (Full-scale Engineered Barrier EXperiment) in situ test which accounts for bentonite swelling and chemical and thermal osmosis. Model results attest the relevance of thermal osmosis and bentonite swelling for the geochemical evolution of the bentonite barrier while chemical osmosis is found to be almost irrelevant. The model has been tested with data collected after the dismantling of heater 1 of the in situ test. The model reproduces reasonably well the measured temperature, relative humidity, water content and inferred geochemical data. However, it fails to mimic the solute concentrations at the heater-bentonite and bentonite-granite interfaces because the model does not account for the volume change of bentonite, the CO{sub 2}(g) degassing and the transport of vapor from the bentonite into the granite. The inferred HCO{sub 3}{sup -} and pH data cannot be explained solely by solute transport, calcite dissolution and protonation/deprotonation by surface complexation, suggesting that such data may be affected also by other reactions.

Zheng, L.; Samper, J.; Montenegro, L.

2011-04-01T23:59:59.000Z

317

THREE-DIMENSIONAL THERMAL MODELING ANALYSIS OF CST MEDIA FOR THE SMALL ION EXCHANGE PROJECT  

SciTech Connect

The Small Column Ion Exchange (SCIX) project is designed to accelerate closure of High Level Waste (HLW) tanks at the Savannah River Site (SRS). The SRS tanks store HLW in three forms: sludge, saltcake, and supernate. An in-tank ion exchange process is being designed to treat supernate and dissolved saltcake waste. Through this process, radioactive cesium from the salt solution is adsorbed into Crystalline Silicotitanate (CST) ion exchange media packed within a flow-through column. A packed column loaded with radioactive cesium generates significant heat from radiolytic decay. The waste supernate solution within the ion exchange bed will boil around 120 C. Solution superheating above the boiling point within the column could lead to violent hazardous energy releases. System heating from loaded CST is also of concern in other process modules, such as the waste tank. Due to tank structural integrity concerns, the wall temperature limit for the SRS waste tanks is 100 C. The transfer of cesium-loaded CST to the tank could result in localized hot spots on the tank floor and walls which may exceed this limit. As a result, thermal modeling calculations have been conducted to predict the maximum temperatures achievable both in the column and in the waste tank. As specified in the associated Technical Task Plan, one objective of the present work was to compute temperature distributions within the ion exchange column module under accident scenarios including loss of salt solution flow through the bed and loss of coolant system flow. The column modeling domain and the scope of the calculations in this case were broadened relative to previous two-dimensional calculations to include vertical temperature distributions within the packed bed of ion exchange media as well as the upper column plenum region containing only fluid. The baseline design conditions and in-column modeling domain for the ion-exchange column module are shown in Figure 1. These evaluations assumed the maximum bounding cesium loading considered possible based on current knowledge regarding CST media and the anticipated feed compositions. Since this cesium loading was considerably higher than the nominal loading conditions in SRS waste, cases with lower loading were also evaluated. Modeling parameters were the same as those used previously unless otherwise indicated. The current model does not capture multi-phase cooling mechanisms operative when solution boiling occurs. This feature is conservative in the sense that it does not account for the large cooling effects associated with phase transfer. However, the potential transfer of heat to the plenum region associated with vertical bubble ascension through the column during boiling is also neglected. Thermal modeling calculations were also performed for the entire waste storage tank for the case where loaded and ground CST was transferred to the tank. The modeling domain used for the in-tank calculations is provided in Figure 2. The in-tank domain is based on SRS Tank 41, which is a Type-IIIA tank. Temperature distributions were evaluated for cylindrical, ground CST mounds located on the tank floor. Media grinding is required prior to vitrification processing of the CST in the SRS Defense Waste Processing Facility (DWPF). The location of the heat source region on the tank floor due to the accumulation of CST material was assumed to be just under the grinder. The shape of the CST mound was assumed to be cylindrical. This shape is believed to be most representative of the actual mound shape formed in the tank, given that submersible mixing pumps will be available for media dispersion. Alternative configurations involving other geometrical shapes for the CST mound were evaluated in the previous work. Sensitivity analysis for the in-tank region was performed for different amounts of CST media. As was the case for the in-column model, the in-tank model does not include multi-phase cooling mechanisms operative when solution boiling occurs. The in-column and the in-tank evaluations incorporated recently updated maximum cesi

Lee, S.; King, W.

2011-09-12T23:59:59.000Z

318

SINGLE-SHELL TANK INTEGRITY PROJECT ANALYSIS OF RECORD-PRELIMINARY MODELING PLAN FOR THERMAL AND OPERATING LOADS  

SciTech Connect

This document is a Phase I deliverable for the Single-Shell Tank Analysis of Record effort. This document is not the Analysis of Record. The intent of this document is to guide the Phase II detailed modeling effort. Preliminary finite element models for each of the tank types were developed and different case studies were performed on one or more of these tank types. Case studies evaluated include thermal loading, waste level variation, the sensitivity of boundary effects (soil radial extent), excavation slope or run to rise ratio, soil stratigraphic (property and layer thickness) variation at different farm locations, and concrete material property variation and their degradation under thermal loads. The preliminary analysis document reviews and preliminary modeling analysis results are reported herein. In addition, this report provides recommendations for the next phase of the SST AOR project, SST detailed modeling. Efforts and results discussed in this report do not include seismic modeling as seismic modeling is covered by a separate report. The combined results of both static and seismic models are required to complete this effort. The SST AOR project supports the US Department of Energy's (DOE) Office of River Protection (ORP) mission for obtaining a better understanding of the structural integrity of Hanford's SSTs. The 149 SSTs, with six different geometries, have experienced a range of operating histories which would require a large number of unique analyses to fully characterize their individual structural integrity. Preliminary modeling evaluations were conducted to determine the number of analyses required for adequate bounding of each of the SST tank types in the Detailed Modeling Phase of the SST AOR Project. The preliminary modeling was conducted in conjunction with the Evaluation Criteria report, Johnson et al. (2010). Reviews of existing documents were conducted at the initial stage of preliminary modeling. These reviews guided the topics that were explored in the SST preliminary modeling. The reviews determined the level of detail necessary to perform the analyses of the SSTs. To guide the Phase II detailed modeling effort, preliminary finite element models for each of the tank types were developed and different case studies were performed on one or more of these tank types. Case studies evaluated include thermal loading, waste level variation, the sensitivity of boundary effects (soil radial extent), excavation slope or run to rise ratio, soil stratigraphic (property and layer thickness) variation at different farm locations, and concrete material property variation and their degradation under thermal loads. Conclusions were derived from case studies on one of the tank types when no additional runs of similar cases on other types of tanks were found necessary to derive those conclusions. The document reviews provided relatively complete temperature histories for Type IV tanks. The temperature history data for Type I, II, and III tanks was almost nonexistent for years prior to 1975. Document reviews indicate that there might be additional useful data in the US Department of Energy, Richland Operations Office (DOE-RL) records in Seattle, WA, and these records need to be reviewed to extract data that might have been disregarded during previous reviews. Thermal stress analyses were conducted using different temperature distribution scenarios on Type IV tanks. Such studies could not be carried out for other tank types due to lack of temperature history data. The results from Type IV tank analyses indicate that factors such as temperature distribution in the tank waste and rate of rise in waste temperature have a significant impact on the thermal stresses in the tank structures. Overall, the conclusion that can drawn from the thermal stress analyses is that these studies should be carried out for all tank types during the detailed analysis phase with temperature values that are reasonably close to the typical temperature histories of the respective tank types. If and/or when additional waste temperature data

RAST RS; RINKER MW; BAPANAALLI SK; DEIBLER JE; GUZMAN-LEONG CE; JOHNSON KI; KARRI NK; PILLI SP; SANBORN SE

2010-10-22T23:59:59.000Z

319

A phenomenological model of thermal-hydraulics of convective boiling during the quenching of hot rod bundles  

Science Conference Proceedings (OSTI)

After completion of the thermal-hydraulic model developed in a companion paper, the authors performed developmental assessment calculation of the model using steady-state and transient post-critical heat flux (CHF) data. This paper discusses the results of those calculations. The overall interfacial drag model predicted reasonable drag coefficients for both the nucleate boiling and the inverted annular flow (IAF) regimes. The predicted pressure drops agreed reasonably well with the measured data of two transient experiments, CCTF Run 14 and a Lehigh reflood test. The thermal-hydraulic model for post-CHF convective heat transfer predicted the rewetting velocities reasonably well for both experiments. The predicted average slope of the wall temperature traces for these tests showed reasonable agreement with the measured data, indicating that the transient-calculated precursory cooling rates agreed with measured data. The hot-patch model, in conjunction with the other thermal-hydraulic models, was capable of modeling the Winfrith post-CHF hot-patch experiments. The hot-patch model kept the wall temperatures at the specified levels in the hot-patch regions and did not allow any quench-front propagation from either the bottom or the top of the test section. The interfacial heat-transfer model tended to slightly underpredict the vapor temperatures. The maximum difference between calculated and measured vapor temperatures was 20%, with a 10% difference for the remainder of the runs considered. The wall-to-fluid heat transfer was predicted reasonably well, and the predicted wall temperatures were in reasonable agreement with measured data with a maximum relative error of less than 13%.

Unal, C.; Nelson, R.

1991-01-01T23:59:59.000Z

320

FAQ 24-Who is responsible for managing depleted uranium?  

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

Who is responsible for managing depleted uranium? Who is responsible for managing depleted uranium? In the United States, the U.S. Department of Energy is responsible for managing...

Note: This page contains sample records for the topic "thermal depletion model" 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

Unsubscribe from the Depleted UF6 E-mail List  

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

Services Unsubscribe Unsubscribe from the Depleted UF6 E-mail List This form allows you to remove yourself from the Depleted UF6 e-mail list. Type your e-mail address here:...

322

U.S. Working Natural Gas Underground Storage Depleted Fields...  

Annual Energy Outlook 2012 (EIA)

Depleted Fields Capacity (Million Cubic Feet) U.S. Working Natural Gas Underground Storage Depleted Fields Capacity (Million Cubic Feet) Decade Year-0 Year-1 Year-2 Year-3 Year-4...

323

New Mexico Natural Gas Number of Underground Storage Depleted...  

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

Depleted Fields Capacity (Number of Elements) New Mexico Natural Gas Number of Underground Storage Depleted Fields Capacity (Number of Elements) Decade Year-0 Year-1 Year-2 Year-3...

324

New Mexico Natural Gas Underground Storage Depleted Fields Capacity...  

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

Depleted Fields Capacity (Million Cubic Feet) New Mexico Natural Gas Underground Storage Depleted Fields Capacity (Million Cubic Feet) Decade Year-0 Year-1 Year-2 Year-3 Year-4...

325

Thermal sensation and comfort models for non-uniform and transient environments: Part II: local comfort of individual body parts  

E-Print Network (OSTI)

3943. [20] Hensel H, Thermal sensation and thermoreceptors1982. [21] Attia M. Thermal pleasantness and temperatureCabanac M. The perception of thermal comfort. International

Zhang, Hui; Arens, Edward; Huizenga, Charlie; Han, Taeyoung

2009-01-01T23:59:59.000Z

326

Light-water-reactor coupled neutronic and thermal-hydraulic codes  

Science Conference Proceedings (OSTI)

An overview is presented of computer codes that model light water reactor cores with coupled neutronics and thermal-hydraulics. This includes codes for transient analysis and codes for steady state analysis which include fuel depletion and fission product buildup. Applications in nuclear design, reactor operations and safety analysis are given and the major codes in use in the USA are identified. The neutronic and thermal-hydraulic methodologies and other code features are outlined for three steady state codes (PDQ7, NODE-P/B and SIMULATE) and four dynamic codes (BNL-TWIGL, MEKIN, RAMONA-3B, RETRAN-02). Speculation as to future trends with such codes is also presented.

Diamond, D.J.

1982-01-01T23:59:59.000Z

327

Selection of a management strategy for depleted uranium hexafluoride  

Science Conference Proceedings (OSTI)

A consequence of the uranium enrichment process used in the United States (US) is the accumulation of a significant amount of depleted uranium hexafluoride (UF{sub 6}). Currently, approximately 560,000 metric tons of the material are stored at three different sites. The US Department of Energy (DOE) has recently initiated a program to consider alternative strategies for the cost-effective and environmentally safe long-term management of this inventory of depleted UF{sub 6}. The program involves a technology and engineering assessment of proposed management options (use/reuse, conversion, storage, or disposal) and an analysis of the potential environmental impacts and life-cycle costs of alternative management strategies. The information obtained from the studies will be used by the DOE to select a preferred long-term management strategy. The selection and implementation of a management strategy will involve consideration of a number of important issues such as environmental, health, and safety effects; the balancing of risks versus costs in a context of reduced government spending; socioeconomic implications, including effects on the domestic and international uranium industry; the technical status of proposed uses or technologies; and public involvement in the decision making process. Because of its provisions for considering a wide range of relevant issues and involving the public, this program has become a model for future DOE materials disposition programs. This paper presents an overview of the Depleted Uranium Hexafluoride Management Program. Technical findings of the program to date are presented, and major issues involved in selecting and implementing a management strategy are discussed.

Patton, S.E.; Hanrahan, E.J.; Bradley, C.E.

1995-09-06T23:59:59.000Z

328

Coarsening of the Sn-Pb Solder Microstructure in Constitutive Model-Based Predictions of Solder Joint Thermal Mechanical Fatigue  

SciTech Connect

Thermal mechanical fatigue (TMF) is an important damage mechanism for solder joints exposed to cyclic temperature environments. Predicting the service reliability of solder joints exposed to such conditions requires two knowledge bases: first, the extent of fatigue damage incurred by the solder microstructure leading up to fatigue crack initiation, must be quantified in both time and space domains. Secondly, fatigue crack initiation and growth must be predicted since this metric determines, explicitly, the loss of solder joint functionality as it pertains to its mechanical fastening as well as electrical continuity roles. This paper will describe recent progress in a research effort to establish a microstructurally-based, constitutive model that predicts TMF deformation to 63Sn-37Pb solder in electronic solder joints up to the crack initiation step. The model is implemented using a finite element setting; therefore, the effects of both global and local thermal expansion mismatch conditions in the joint that would arise from temperature cycling.

Vianco, P.T.; Burchett, S.N.; Neilsen, M.K.; Rejent, J.A.; Frear, D.R.

1999-04-12T23:59:59.000Z

329

Thermal sensation and comfort models for non-uniform and transient environments: Part III: whole-body sensation and comfort  

E-Print Network (OSTI)

Magnitude estimates of thermal discomfort during transientsJ, Rohles FH, Nevins RG. Thermal comfort (thermally neutral)1.3.1 - [10] Fanger PO. Thermal comfort. NY: McGraw-Hill;

Zhang, Hui; Arens, Edward; Huizenga, Charlie; Han, Taeyoung

2009-01-01T23:59:59.000Z

330

Three-Dimensional Thermal-Electrochemical Coupled Model for Spirally Wound Large-Format Lithium-Ion Batteries (Presentation)  

DOE Green Energy (OSTI)

This presentation discusses the behavior of spirally wound large-format Li-ion batteries with respect to their design. The objectives of the study include developing thermal and electrochemical models resolving 3-dimensional spirally wound structures of cylindrical cells, understanding the mechanisms and interactions between local electrochemical reactions and macroscopic heat and electron transfers, and developing a tool and methodology to support macroscopic designs of cylindrical Li-ion battery cells.

Lee, K. J.; Smith K.; Kim, G. H.

2011-04-01T23:59:59.000Z

331

A modern depleted uranium manufacturing facility  

SciTech Connect

The Specific Manufacturing Capabilities (SMC) Project located at the Idaho National Engineering Laboratory (INEL) and operated by Lockheed Martin Idaho Technologies Co. (LMIT) for the Department of Energy (DOE) manufactures depleted uranium for use in the U.S. Army MIA2 Abrams Heavy Tank Armor Program. Since 1986, SMC has fabricated more than 12 million pounds of depleted uranium (DU) products in a multitude of shapes and sizes with varying metallurgical properties while maintaining security, environmental, health and safety requirements. During initial facility design in the early 1980`s, emphasis on employee safety, radiation control and environmental consciousness was gaining momentum throughout the DOE complex. This fact coupled with security and production requirements forced design efforts to focus on incorporating automation, local containment and computerized material accountability at all work stations. The result was a fully automated production facility engineered to manufacture DU armor packages with virtually no human contact while maintaining security, traceability and quality requirements. This hands off approach to handling depleted uranium resulted in minimal radiation exposures and employee injuries. Construction of the manufacturing facility was complete in early 1986 with the first armor package certified in October 1986. Rolling facility construction was completed in 1987 with the first certified plate produced in the fall of 1988. Since 1988 the rolling and manufacturing facilities have delivered more than 2600 armor packages on schedule with 100% final product quality acceptance. During this period there was an annual average of only 2.2 lost time incidents and a single individual maximum radiation exposure of 150 mrem. SMC is an example of designing and operating a facility that meets regulatory requirements with respect to national security, radiation control and personnel safety while achieving production schedules and product quality.

Zagula, T.A.

1995-07-01T23:59:59.000Z

332

FAQ 25-What are the options for managing depleted uranium in...  

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

options for managing depleted uranium in the future? What are the options for managing depleted uranium in the future? The options for managing depleted uranium were evaluated in...

333

Evaluation of uncertainties due to hydrogeological modeling and groundwater flow analysis: Steady flow, transient flow, and thermal studies  

SciTech Connect

Starting with regional geographic, geologic, surface and subsurface hydrologic, and geophysical data for the Tono area in Gifu, Japan, we develop an effective continuum model to simulate subsurface flow and transport in a 4 km by 6 km by 3 km thick fractured granite rock mass overlain by sedimentary layers. Individual fractures are not modeled explicitly. Rather, continuum permeability and porosity distributions are assigned stochastically, based on well-test data and fracture density measurements. Lithologic layering and one major fault, the Tsukiyoshi Fault, are assigned deterministically. We conduct three different studies: (1) the so-called base case, in which the model simulates the steady-state groundwater flow through the site, and then stream trace analysis is used to calculate travel times to the model boundary from specified release points; (2) simulations of transient flow during long term pump tests (LTPT) using the base-case model; and (3) thermal studies in which coupled heat flow and fluid flow are modeled, to examine the effects of the geothermal gradient on groundwater flow. The base-case study indicates that the choice of open or closed lateral boundaries has a strong influence on the regional groundwater flow patterns produced by the models, but no field data exist that can be used to determine which boundary conditions are more realistic. The LTPT study cannot be used to distinguish between the alternative boundary conditions, because the pumping rate is too small to produce an analyzable pressure response at the model boundaries. In contrast, the thermal study shows that the temperature distributions produced by the open and closed models differ greatly. Comparison with borehole temperature data may be used to eliminate the closed model from further consideration.

Doughty, Christine; Karasaki, Kenzi

2002-12-11T23:59:59.000Z

334

Summary of: Simulating the Value of Concentrating Solar Power with Thermal Energy Storage in a Production Cost Model (Presentation)  

DOE Green Energy (OSTI)

Concentrating solar power (CSP) deployed with thermal energy storage (TES) provides a dispatchable source of renewable energy. The value of CSP with TES, as with other potential generation resources, needs to be established using traditional utility planning tools. Production cost models, which simulate the operation of grid, are often used to estimate the operational value of different generation mixes. CSP with TES has historically had limited analysis in commercial production simulations. This document describes the implementation of CSP with TES in a commercial production cost model. It also describes the simulation of grid operations with CSP in a test system consisting of two balancing areas located primarily in Colorado.

Denholm, P.; Hummon, M.

2013-02-01T23:59:59.000Z

335

An improved numerical model for the investigation of thermal hydraulic phenomena with applications to LMR reactor components  

SciTech Connect

A basic limited scope, fast-running computer model is presented for the solution of single phase two-dimensional transients in thermally coupled incompressible fluid flow problems. The governing equations and the two-equation transport model (k-{epsilon}) of turbulence are reduced to a set of linear algebraic equations in an implicit finite difference scheme, based on the control volume approach. These equations are solved iteratively in a line-by-line procedure using the tri-diagonal matrix algorithm. The numerical formulation and general calculational procedure are described in detail. The calculations show good agreement when compared with experimental data and other independent analyses.

Chan, B.C.; Kennett, R.J.; Van Tuyle, G.J.

1992-01-01T23:59:59.000Z

336

An improved numerical model for the investigation of thermal hydraulic phenomena with applications to LMR reactor components  

SciTech Connect

A basic limited scope, fast-running computer model is presented for the solution of single phase two-dimensional transients in thermally coupled incompressible fluid flow problems. The governing equations and the two-equation transport model (k-{epsilon}) of turbulence are reduced to a set of linear algebraic equations in an implicit finite difference scheme, based on the control volume approach. These equations are solved iteratively in a line-by-line procedure using the tri-diagonal matrix algorithm. The numerical formulation and general calculational procedure are described in detail. The calculations show good agreement when compared with experimental data and other independent analyses.

Chan, B.C.; Kennett, R.J.; Van Tuyle, G.J.

1992-08-01T23:59:59.000Z

337

The scale analysis sequence for LWR fuel depletion  

Science Conference Proceedings (OSTI)

The SCALE (Standardized Computer Analyses for Licensing Evaluation) code system is used extensively to perform away-from-reactor safety analysis (particularly criticality safety, shielding, heat transfer analyses) for spent light water reactor (LWR) fuel. Spent fuel characteristics such as radiation sources, heat generation sources, and isotopic concentrations can be computed within SCALE using the SAS2 control module. A significantly enhanced version of the SAS2 control module, which is denoted as SAS2H, has been made available with the release of SCALE-4. For each time-dependent fuel composition, SAS2H performs one-dimensional (1-D) neutron transport analyses (via XSDRNPM-S) of the reactor fuel assembly using a two-part procedure with two separate unit-cell-lattice models. The cross sections derived from a transport analysis at each time step are used in a point-depletion computation (via ORIGEN-S) that produces the burnup-dependent fuel composition to be used in the next spectral calculation. A final ORIGEN-S case is used to perform the complete depletion/decay analysis using the burnup-dependent cross sections. The techniques used by SAS2H and two recent applications of the code are reviewed in this paper. 17 refs., 5 figs., 5 tabs.

Hermann, O.W.; Parks, C.V.

1991-01-01T23:59:59.000Z

338

On the Presence of Depleted Zones in Platinum  

SciTech Connect

In the bombardment of materials with heavy particles a large amount of energy can be deposited in a very small region by a primary knock-on atom and the local atomic arrangement can be thereby drastically disrupted. Various measurements of physical properties of such irradiated materials indicate the presence of distributions of defects which are removed in a step-like manner by annealing. One of the more interesting physical property changes accompanying fast particle irradiation is the attendant change in mechanical properties of irradiated crystals. The defect which is responsible for the mechanical property changes of irradiated crystals is only removed at high temperatures, temperatures coresponding to self diffusion. This observation, as well as others, has led to the model of a depleted zone as being responsible for the changes of mechanical properties of irradiated crystals. A depleted zone is envisioned as a region of crystal where a high local concentration of point defects exists - a belt of interstitials surrounding a multiply connected complex of vacancy clusters. We would like to present here some evidence which lends support to the existence of such defects.

Attardo, M J; Galligan, J M

1966-08-05T23:59:59.000Z

339

Efficient power modeling and software thermal sensing for runtime temperature monitoring  

Science Conference Proceedings (OSTI)

The evolution of microprocessors has been hindered by increasing power consumption and heat dissipation on die. An excessive amount of heat creates reliability problems, reduces the lifetime of a processor, and elevates the cost of cooling and packaging ... Keywords: Power, thermal

Wei Wu; Lingling Jin; Jun Yang; Pu Liu; Sheldon X.-D. Tan

2007-08-01T23:59:59.000Z

340

A Two-Level Model of a Thermally Forced Ocean Basin  

Science Conference Proceedings (OSTI)

Some simple solutions (mostly analytic) are presented for the large-scale baroclinic response to thermal forcing on a mid-latitude beta-plane. Surface heat flux is parameterized as (TA–TT)/tau;, with atmospheric temperature TA prescribed as a ...

M. K. Davey

1983-02-01T23:59:59.000Z

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


341

On Haney-Type Surface Thermal Boundary Conditions for Ocean Circulation Models  

Science Conference Proceedings (OSTI)

Haney-type surface thermal boundary conditions linearly connect net downward surface heat flux Q to air–sea temperature difference (gradient-type condition) ?T1 or to climate/synoptic sea temperature difference (restoring-type condition) ?T2 by a ...

Peter C. Chu; Yuchun Chen; Shihua Lu

1998-05-01T23:59:59.000Z

342

High-Resolution Numerical Modeling of Thermally Driven Slope Winds in a Valley with Strong Capping  

Science Conference Proceedings (OSTI)

The complete day–night cycle of the circulation over a slope under simplified idealized boundary conditions is investigated by means of large-eddy simulations (LES). The thermal forcing is given with a time-varying law for the surface ...

Franco Catalano; Antonio Cenedese

2010-09-01T23:59:59.000Z

343

A Model of Sea Level Rise Caused by Ocean Thermal Expansion  

Science Conference Proceedings (OSTI)

Warming of the atmosphere as a result of an increased concentration of greenhouse gases is expected to lead to a significant rise is global sea level. We present estimates of the component of this sea level rise caused by thermal expansion of the ...

John A. Church; J. Stuart Godfrey; David R. Jackett; Trevor J. McDougall

1991-04-01T23:59:59.000Z

344

COBRA-SFS (Spent Fuel Storage): A thermal-hydraulic analysis computer code: Volume 1, Mathematical models and solution method  

Science Conference Proceedings (OSTI)

COBRA-SFS (Spent Fuel Storage) is a general thermal-hydraulic analysis computer code used to predict temperatures and velocities in a wide variety of systems. The code was refined and specialized for spent fuel storage system analyses for the US Department of Energy's Commercial Spent Fuel Management Program. The finite-volume equations governing mass, momentum, and energy conservation are written for an incompressible, single-phase fluid. The flow equations model a wide range of conditions including natural circulation. The energy equations include the effects of solid and fluid conduction, natural convection, and thermal radiation. The COBRA-SFS code is structured to perform both steady-state and transient calculations: however, the transient capability has not yet been validated. This volume describes the finite-volume equations and the method used to solve these equations. It is directed toward the user who is interested in gaining a more complete understanding of these methods.

Rector, D.R.; Wheeler, C.L.; Lombardo, N.J.

1986-11-01T23:59:59.000Z

345

Steady-State and Transient Thermal Modeling of Oil-Immersed Bushing-type Current Transformers in Power Transformers and Circuit Brea kers  

Science Conference Proceedings (OSTI)

This report documents methods of calculating the thermal rating of bushing-type Current Transformers (CTs). Researchers compared mathematical models to experimental results and evaluated the limits on CT winding temperature experimentally.

2009-02-09T23:59:59.000Z

346

Midtemperature solar systems test facility predictions for thermal performance based on test data. Polisolar Model POL solar collector with glass reflector surface  

DOE Green Energy (OSTI)

Thermal performance predictions based on test data are presented for the Polisolar Model POL solar collector, with glass reflector surfaces, for three output temperatures at five cities in the United States.

Harrison, T.D.

1981-05-01T23:59:59.000Z

347

Overview of Depleted Uranium Hexafluoride Management Program  

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

DOE's DUF DOE's DUF 6 Cylinder Inventory a Location Number of Cylinders DUF 6 (MT) b Paducah, Kentucky 36,910 450,000 Portsmouth, Ohio 16,041 198,000 Oak Ridge (ETTP), Tennessee 4,683 56,000 Total 57,634 704,000 a The DOE inventory includes DUF 6 generated by the government, as well as DUF 6 transferred from U.S. Enrichment Corporation pursuant to two memoranda of agreement. b A metric ton (MT) is equal to 1,000 kilograms, or 2,200 pounds. Overview of Depleted Uranium Hexafluoride Management Program Over the last four decades, large quantities of uranium were processed by gaseous diffusion to produce enriched uranium for U.S. national defense and civilian purposes. The gaseous diffusion process uses uranium in the form of uranium hexafluoride (UF 6 ), primarily because UF 6 can conveniently be used in

348

Regulation of New Depleted Uranium Uses  

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

2-5 2-5 Regulation of New Depleted Uranium Uses Environmental Assessment Division Argonne National Laboratory Operated by The University of Chicago, under Contract W-31-109-Eng-38, for the United States Department of Energy DISCLAIMER 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 The University of Chicago, nor any of their employees or officers, 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,

349

Steady Linear Response to Thermal Forcing of an Anomaly Model with an Asymmetric Climatology  

Science Conference Proceedings (OSTI)

An anomaly model linearized around the observed winter climatology is used to study the steady response of the atmosphere to diabatic heating. The model is an R7, nine vertical levels, primitive equations, fully spectral model, derived from the ...

A. Navarra

1990-01-01T23:59:59.000Z

350

Arc Flash Issues in Transmission and Substation Environments: Modeling of Incident Thermal Energy of Long Arcs  

Science Conference Proceedings (OSTI)

Arc flashes are a serious hazard that may put people in life-threatening situations and cause great damage to existing assets. The National Electrical Safety Code (NESC) and the Occupational Safety and Health Administration (OSHA) introduced requirements for electric utilities to perform arc flash hazard assessment of their facilities operating at and above 1000 V. Most methods available at this time for analyzing the incident thermal energy of arc flash were developed for low and medium-voltage industri...

2011-12-20T23:59:59.000Z

351

Thermal and Corona Models of Overhead Transmission Lines Operating at High Temperatures  

Science Conference Proceedings (OSTI)

In order to provide electric power to a society that is continuously increasing its power consumption, without having to sustain huge capital expenditures for new infrastructure, the power industry is pushing more power through existing lines. Although this results in conductors operating at higher temperatures, which in turn results in higher thermal and mechanical losses, the industry is finding it to be a cost-effective approach when compared to alternatives. The demand for electric power over transmi...

2008-12-23T23:59:59.000Z

352

Thermal sensation and comfort in transient non-uniform thermal environments  

E-Print Network (OSTI)

cooling applied cooling removed Thermal Sensation Skincooling = 14°C cooling removed Thermal Sensation We measureda hand cooling test Models to predict thermal sensation and

Zhang, Hui; Huizenga, Charlie; Arens, Edward; Wang, Danni

2004-01-01T23:59:59.000Z

353

Rule-based Mamdani-type fuzzy modelling of thermal performance of multi-layer precast concrete panels used in residential buildings in Turkey  

Science Conference Proceedings (OSTI)

Heat insulation applied on outer wall surfaces of buildings for the purpose of conserving energy, can be analyzed experimentally, mathematically and by using simulation modelling. In this study, simulation modelling of insulation layer (d"2), for residential ... Keywords: Insulation, Prefabricated panel, Rule-based Mamdani-type fuzzy modelling, Thermal analysis

M. Tosun; K. Dincer; S. Baskaya

2011-05-01T23:59:59.000Z

354

Thermal sensation and comfort models for non-uniform and transient environments: Part III: whole-body sensation and comfort  

E-Print Network (OSTI)

to local heating and cooling [4,5], thermal sensation andbody heating and cooling. Journal of Thermal Biology 2004;body-segment cooling or heating b. thermal sensation scale

Zhang, Hui; Arens, Edward; Huizenga, Charlie; Han, Taeyoung

2009-01-01T23:59:59.000Z

355

Thermal sensation and comfort models for non-uniform and transient environments: Part I: local sensation of individual body parts  

E-Print Network (OSTI)

to local heating and cooling [13,15], thermal sensation andbody heating and cooling. Journal of Thermal Biology 2004;local cooling or heating test, when the body’s thermal state

Zhang, Hui; Arens, Edward; Huizenga, Charlie; Han, Taeyoung

2009-01-01T23:59:59.000Z

356

Thermal sensation and comfort models for non-uniform and transient environments: Part II: local comfort of individual body parts  

E-Print Network (OSTI)

to local heating and cooling [18,19], thermal sensation andbody heating and cooling. Journal of Thermal Biology 2004;b. pelvis cooling or heating c. thermal comfort scale Figure

Zhang, Hui; Arens, Edward; Huizenga, Charlie; Han, Taeyoung

2009-01-01T23:59:59.000Z

357

Modeling, design and thermal performance of a BIPV/T system thermally coupled with a ventilated concrete slab in a low energy solar house: Part 1, BIPV/T system and house energy concept  

SciTech Connect

This paper is the first of two papers that describe the modeling, design, and performance assessment based on monitored data of a building-integrated photovoltaic-thermal (BIPV/T) system thermally coupled with a ventilated concrete slab (VCS) in a prefabricated, two-storey detached, low energy solar house. This house, with a design goal of near net-zero annual energy consumption, was constructed in 2007 in Eastman, Quebec, Canada - a cold climate area. Several novel solar technologies are integrated into the house and with passive solar design to reach this goal. An air-based open-loop BIPV/T system produces electricity and collects heat simultaneously. Building-integrated thermal mass is utilized both in passive and active forms. Distributed thermal mass in the direct gain area and relatively large south facing triple-glazed windows (about 9% of floor area) are employed to collect and store passive solar gains. An active thermal energy storage system (TES) stores part of the collected thermal energy from the BIPV/T system, thus reducing the energy consumption of the house ground source heat pump heating system. This paper focuses on the BIPV/T system and the integrated energy concept of the house. Monitored data indicate that the BIPV/T system has a typical efficiency of about 20% for thermal energy collection, and the annual space heating energy consumption of the house is about 5% of the national average. A thermal model of the BIPV/T system suitable for preliminary design and control of the airflow is developed and verified with monitored data. (author)

Chen, Yuxiang; Athienitis, A.K.; Galal, Khaled [Dept. of Building, Civil and Environmental Engineering, Concordia University, 1455 De Maisonneuve West, EV6.139, Montreal, Quebec (Canada)

2010-11-15T23:59:59.000Z

358

A solar thermal cooling and heating system for a building: Experimental and model based performance analysis and design  

Science Conference Proceedings (OSTI)

A solar thermal cooling and heating system at Carnegie Mellon University was studied through its design, installation, modeling, and evaluation to deal with the question of how solar energy might most effectively be used in supplying energy for the operation of a building. This solar cooling and heating system incorporates 52 m{sup 2} of linear parabolic trough solar collectors; a 16 kW double effect, water-lithium bromide (LiBr) absorption chiller, and a heat recovery heat exchanger with their circulation pumps and control valves. It generates chilled and heated water, dependent on the season, for space cooling and heating. This system is the smallest high temperature solar cooling system in the world. Till now, only this system of the kind has been successfully operated for more than one year. Performance of the system has been tested and the measured data were used to verify system performance models developed in the TRaNsient SYstem Simulation program (TRNSYS). On the basis of the installed solar system, base case performance models were programmed; and then they were modified and extended to investigate measures for improving system performance. The measures included changes in the area and orientation of the solar collectors, the inclusion of thermal storage in the system, changes in the pipe diameter and length, and various system operational control strategies. It was found that this solar thermal system could potentially supply 39% of cooling and 20% of heating energy for this building space in Pittsburgh, PA, if it included a properly sized storage tank and short, low diameter connecting pipes. Guidelines for the design and operation of an efficient and effective solar cooling and heating system for a given building space have been provided. (author)

Qu, Ming [School of Civil Engineering, Purdue University, 550 Stadium Mall Drive, West Lafayette, IN 47907-2051 (United States); Yin, Hongxi [School of Engineering Education, Purdue University, 701 W. Stadium Ave., West Lafayette, IN 47907-2061 (United States); Archer, David H. [Department of Mechanical Engineering, Carnegie Mellon University, 5000 Forbes Ave., Pittsburgh, PA 15213 (United States)

2010-02-15T23:59:59.000Z

359

Thermal modeling of the Clear Lake magmatic system, California: Implications for conventional and hot dry rock geothermal development  

Science Conference Proceedings (OSTI)

The combination of recent volcanism, high heat flow ({ge} HFU or 167 mW/m{sup 2}), and high conductive geothermal gradient (up to 120{degree} C/km) makes the Clear Lake region of northern California one of the best prospects for hot dry rock (HDR) geothermal development in the US. The lack of permeability in exploration wells and lack of evidence for widespread geothermal reservoirs north of the Collayomi fault zone are not reassuring indications for conventional geothermal development. This report summarizes results of thermal modeling of the Clear Lake magmatic system, and discusses implications for HDR site selection in the region. The thermal models incorporate a wide range of constraints including the distribution and nature of volcanism in time and space, water and gas geochemistry, well data, and geophysical surveys. The nature of upper crustal magma bodies at Clear Lake is inferred from studying sequences of related silicic lavas, which tell a story of multistage mixing of silicic and mafic magma in clusters of small upper crustal chambers. Thermobarometry on metamorphic xenoliths yield temperature and pressure estimates of {approximately}780--900 C and 4--6 kb respectively, indicating that at least a portion of the deep magma system resided at depths from 14 to 21 km (9 to 12 mi). The results of thermal modeling support previous assessments of the high HDR potential of the area, and suggest the possibility that granitic bodies similar to The Geysers felsite may underlie much of the Clear Lake region at depths as little as 3--6 km. This is significant because future HDR reservoirs could potentially be sited in relatively shallow granitoid plutons rather than in structurally complex Franciscan basement rocks.

Stimac, J.; Goff, F.; Wohletz, K.

1997-06-01T23:59:59.000Z

360

Press Release: DOE Seeks Public Input for Depleted Uranium Hexafluorid...  

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

Perry, (865) 576-0885 September 24, 2001 www.oakridge.doe.gov DOE SEEKS PUBLIC INPUT FOR DEPLETED URANIUM HEXAFLUORIDE ENVIRONMENTAL IMPACT STATEMENT Public Meetings Planned in...

Note: This page contains sample records for the topic "thermal depletion model" 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

DOE Selects Contractor for Depleted Hexafluoride Conversion Project...  

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

in Paducah, Kentucky and Portsmouth, Ohio. For several decades DOE was responsible for uranium enrichment, the uranium hexafluoride depleted in the 235U isotope (typically down...

362

Environmental Risks of Depleted UF6-related Manufacturing Activities  

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

and operation of a facility to fabricate representative products containing depleted uranium. Impacts Analyzed in the PEIS The PEIS evaluated the general environmental impacts...

363

Health Risks Associated with Disposal of Depleted Uranium  

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

Disposal DUF6 Health Risks line line Accidents Storage Conversion Manufacturing Disposal Transportation Disposal of Depleted Uranium A discussion of risks associated with disposal...

364

Environmental Impacts of Options for Disposal of Depleted Uranium...  

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

study by Oak Ridge National Laboratory evaluated the acceptability of several depleted uranium conversion products at potential LLW disposal sites to provide a basis for DOE...

365

Depleted UF6 Management Information Network - A resource for...  

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

is an online repository of information about the U.S. Department of Energy's (DOE's) inventory of depleted uranium hexafluoride (DUF6), a product of the uranium enrichment...

366

THERMO-HYDRO-MECHANICAL MODELING OF WORKING FLUID INJECTION AND THERMAL ENERGY EXTRACTION IN EGS FRACTURES AND ROCK MATRIX  

DOE Green Energy (OSTI)

Development of enhanced geothermal systems (EGS) will require creation of a reservoir of sufficient volume to enable commercial-scale heat transfer from the reservoir rocks to the working fluid. A key assumption associated with reservoir creation/stimulation is that sufficient rock volumes can be hydraulically fractured via both tensile and shear failure, and more importantly by reactivation of naturally existing fractures (by shearing), to create the reservoir. The advancement of EGS greatly depends on our understanding of the dynamics of the intimately coupled rock-fracture-fluid-heat system and our ability to reliably predict how reservoirs behave under stimulation and production. Reliable performance predictions of EGS reservoirs require accurate and robust modeling for strongly coupled thermal-hydrological-mechanical (THM) processes. Conventionally, these types of problems have been solved using operator-splitting methods, usually by coupling a subsurface flow and heat transport simulators with a solid mechanics simulator via input files. An alternative approach is to solve the system of nonlinear partial differential equations that govern multiphase fluid flow, heat transport, and rock mechanics simultaneously, using a fully coupled, fully implicit solution procedure, in which all solution variables (pressure, enthalpy, and rock displacement fields) are solved simultaneously. This paper describes numerical simulations used to investigate the poro- and thermal- elastic effects of working fluid injection and thermal energy extraction on the properties of the fractures and rock matrix of a hypothetical EGS reservoir, using a novel simulation software FALCON (Podgorney et al., 2011), a finite element based simulator solving fully coupled multiphase fluid flow, heat transport, rock deformation, and fracturing using a global implicit approach. Investigations are also conducted on how these poro- and thermal-elastic effects are related to fracture permeability evolution.

Robert Podgorney; Chuan Lu; Hai Huang

2012-01-01T23:59:59.000Z

367

Advanced battery thermal management for electrical-drive vehicles using reciprocating cooling flow and spatial-resolution, lumped-capacitance thermal model.  

E-Print Network (OSTI)

?? The thermal management of traction battery systems for electrical-drive vehicles directly affects vehicle dynamic performance, long-term durability and cost of the battery systems. The… (more)

Mahamud, Rajib

2011-01-01T23:59:59.000Z

368

Thermal decoupling and the smallest subhalo mass in dark matter models with Sommerfeld-enhanced annihilation rates  

E-Print Network (OSTI)

We consider dark matter consisting of weakly interacting massive particles (WIMPs) and revisit in detail its thermal evolution in the early universe, with a particular focus on models where the annihilation rate is enhanced by the Sommerfeld effect. After chemical decoupling, or freeze-out, dark matter no longer annihilates but is still kept in local thermal equilibrium due to scattering events with the much more abundant standard model particles. During kinetic decoupling, even these processes stop to be effective, which eventually sets the scale for a small-scale cutoff in the matter density fluctuations. Afterwards, the WIMP temperature decreases more quickly than the heat bath temperature, which causes dark matter to reenter an era of annihilation if the cross-section is enhanced by the Sommerfeld effect. Here, we give a detailed and self-consistent description of these effects. As an application, we consider the phenomenology of simple leptophilic models that have been discussed in the literature and find that the relic abundance can be affected by as much two orders of magnitude or more. We also compute the mass of the smallest dark matter subhalos in these models and find it to be in the range of about 10^{-10} to 10 solar masses; even much larger cutoff values are possible if the WIMPs couple to force carriers lighter than about 100 MeV. We point out that a precise determination of the cutoff mass allows to infer new limits on the model parameters, in particular from gamma-ray observations of galaxy clusters, that are highly complementary to existing constraints from g-2 or beam dump experiments.

Laura G. van den Aarssen; Torsten Bringmann; Yasar C. Goedecke

2012-02-24T23:59:59.000Z

369

Development of a Zero-Dimensional Mesoscale Thermal Model for Urban Climate  

Science Conference Proceedings (OSTI)

A simple energy balance model is created for use in developing mitigation strategies for the urban heat island effect. The model is initially applied to the city of Phoenix, Arizona. There are six primary contributions to the overall energy ...

Humberto R. Silva; Rahul Bhardwaj; Patrick E. Phelan; Jay S. Golden; Susanne Grossman-Clarke

2009-03-01T23:59:59.000Z

370

Multi-Dimensional Electrochemical-Thermal Coupled Model of Large Format Cylindrical Lithium Ion Cells (Presentation)  

DOE Green Energy (OSTI)

Presentation on 3-D modeling of lithium-ion cells used in plug-in hyybrid electric vehicle batteries. 3-D models provide better understanding of cell design, operation, and management.

Kim, G.-H.; Smith, K.

2007-10-01T23:59:59.000Z

371

Numerical Simulation of a Buoyant Thermal Using the k-? Turbulence Model  

Science Conference Proceedings (OSTI)

Possibilities for describing turbulent mixing processes through the use of the two-equation k-? model modified to take into account the effects of streamline curvature and buoyancy are discussed. It is shown that one of the k-? model constants ...

Y. A. Dovgalyuk; M. A. Zatevakhin; E. N. Stankova

1994-09-01T23:59:59.000Z

372

A two-stage planning model for power scheduling in a hydro-thermal system under uncertainty  

E-Print Network (OSTI)

Abstract. A two-stage stochastic programming model for the short- or mid-term cost-optimal electric power production planning is developed. We consider the power generation in a hydro-thermal generation system under uncertainty in demand (or load) and prices for fuel and delivery contracts. The model involves a large number of mixed-integer (stochastic) decision variables and constraints linking time periods and operating power units. A stochastic Lagrangian relaxation scheme is designed by assigning (stochastic) multipliers to all constraints that couple power units. It is assumed that the stochastic load and price processes are given (or approximated) by a finite number of realizations (scenarios). Solving the dual by a bundle subgradient method leads to a successive decomposition into stochastic single unit subproblems. The stochastic thermal and hydro subproblems are solved by a stochastic dynamic programming technique and by a specific descent algorithm, respectively. A Lagrangian heuristics that provides approximate solutions for the primal problem is developed. Numerical results are presented for realistic data from a German power utility and for numbers of scenarios ranging from 5 to 100 and a time horizon of 168 hours. The sizes of the corresponding optimization problems go up to 400.000 binary and 650.000 continuous variables, and more than 1.300.000 constraints. Keywords: stochastic programming, Lagrangian relaxation, unit commitment

Robert Nürnberg; Werner Römisch

2002-01-01T23:59:59.000Z

373

Application of Distribution Transformer Thermal Life Models to Electrified Vehicle Charging Loads Using Monte-Carlo Method: Preprint  

DOE Green Energy (OSTI)

Concentrated purchasing patterns of plug-in vehicles may result in localized distribution transformer overload scenarios. Prolonged periods of transformer overloading causes service life decrements, and in worst-case scenarios, results in tripped thermal relays and residential service outages. This analysis will review distribution transformer load models developed in the IEC 60076 standard, and apply the model to a neighborhood with plug-in hybrids. Residential distribution transformers are sized such that night-time cooling provides thermal recovery from heavy load conditions during the daytime utility peak. It is expected that PHEVs will primarily be charged at night in a residential setting. If not managed properly, some distribution transformers could become overloaded, leading to a reduction in transformer life expectancy, thus increasing costs to utilities and consumers. A Monte-Carlo scheme simulated each day of the year, evaluating 100 load scenarios as it swept through the following variables: number of vehicle per transformer, transformer size, and charging rate. A general method for determining expected transformer aging rate will be developed, based on the energy needs of plug-in vehicles loading a residential transformer.

Kuss, M.; Markel, T.; Kramer, W.

2011-01-01T23:59:59.000Z

374

A finite element analysis modeling tool for solid oxide fuel cell development: coupled electrochemistry, thermal and flow analysis in MARC®  

Science Conference Proceedings (OSTI)

A 3D simulation tool for modeling solid oxide fuel cells is described. The tool combines the versatility and efficiency of a commercial finite element analysis code, MARC{reg_sign}, with an in-house developed robust and flexible electrochemical (EC) module. Based upon characteristic parameters obtained experimentally and assigned by the user, the EC module calculates the current density distribution, heat generation, and fuel and oxidant species concentration, taking the temperature profile provided by MARC{reg_sign} and operating conditions such as the fuel and oxidant flow rate and the total stack output voltage or current as the input. MARC{reg_sign} performs flow and thermal analyses based on the initial and boundary thermal and flow conditions and the heat generation calculated by the EC module. The main coupling between MARC{reg_sign} and EC is for MARC{reg_sign} to supply the temperature field to EC and for EC to give the heat generation profile to MARC{reg_sign}. The loosely coupled, iterative scheme is advantageous in terms of memory requirement, numerical stability and computational efficiency. The coupling is iterated to self-consistency for a steady-state solution. Sample results for steady states as well as the startup process for stacks with different flow designs are presented to illustrate the modeling capability and numerical performance characteristic of the simulation tool.

Khaleel, Mohammad A.; Lin, Zijing; Singh, Prabhakar; Surdoval, Wayne; Collin, D

2004-05-03T23:59:59.000Z

375

EXPERIMENTAL VERIFICATION OF THE THREE-DIMENSIONAL THERMAL-HYDRAULIC MODELS IN THE BEST-ESTIMATE CODE BAGIRA.  

Science Conference Proceedings (OSTI)

In this paper we present verification results of the BAGIRA code that was performed using data from integral thermal-hydraulic experimental test facilities as well as data obtained from operating nuclear power plants. BAGIRA is a three-dimensional numerical best-estimate code that includes non-homogeneous modeling. Special consideration was given to the recently completed experimental data from the PSB-VVER integral test facility (EREC, Electrogorsk, Russia)--a new Russian large-scale four-loop unit, which has been designed to model the primary circuits of VVER-1000 type reactors. It is demonstrated that the code BAGIRA can be used to analyze nuclear reactor behavior under normal and accident conditions.

KALINICHENKO,S.D.KROSHILIN,A.E.KROSHILIN,V.E.SMIRNOV,A.V.KOHUT,P.

2004-03-15T23:59:59.000Z

376

Development of models for the sodium version of the two-phase three-dimensional thermal hydraulics code THERMIT. [LMFBR  

SciTech Connect

Several different models and correlations were developed and incorporated in the sodium version of THERMIT, a thermal-hydraulics code written at MIT for the purpose of analyzing transients under LMFBR conditions. This includes: a mechanism for the inclusion of radial heat conduction in the sodium coolant as well as radial heat loss to the structure surrounding the test section. The fuel rod conduction scheme was modified to allow for more flexibility in modelling the gas plenum regions and fuel restructuring. The formulas for mass and momentum exchange between the liquid and vapor phases were improved. The single phase and two phase friction factors were replaced by correlations more appropriate to LMFBR assembly geometry.

Wilson, G.J.; Kazimi, M.S.

1980-05-01T23:59:59.000Z

377

Analysis of Hydrogen Depletion Using a Scaled Passive Autocatalytic Recombiner  

DOE Green Energy (OSTI)

Hydrogen depletion tests of a scaled passive autocatalytic recombine (pAR) were performed in the Surtsey test vessel at Sandia National Laboratories (SNL). The experiments were used to determine the hydrogen depletion rate of a PAR in the presence of steam and also to evaluate the effect of scale (number of cartridges) on the PAR performance at both low and high hydrogen concentrations.

Blanchat, T.K.; Malliakos, A.

1998-10-28T23:59:59.000Z

378

Real-Time Forcast Model Analysis of Daily Average Building Load for a Thermal Storage System Control  

E-Print Network (OSTI)

Thermal storage systems were originally designed to shift the on-peak cooling production to off-peak cooling production to reduce the on-peak demand. Based on the current electricity charging structure, the reduction of both on-peak and off-peak demands is becoming an exceedingly important issue. Reduction of both on-peak and off-peak demands can also extend the life span and defer or eliminate the replacement of power transformers due to potential shortage of building power capacity with anticipated equipment load increases. The next day daily average electricity demand is a critical set point to operate chillers and associated pumps at the appropriate time. For this paper, a mathematic analysis was conducted for annual daily average cooling of a building and three real-time building load forecasting models were developed. They are first-order autogressive model, random walk model and linear regression model. Finally, the comparison of results show the random walk model provides the best forecast.

Song, L.; Joo, I. S.; Guwana, S.

2009-11-01T23:59:59.000Z

379

Use of depleted uranium metal as cask shielding in high-level waste storage, transport, and disposal systems  

SciTech Connect

The US DOE has amassed over 555,000 metric tons of depleted uranium from its uranium enrichment operations. Rather than dispose of this depleted uranium as waste, this study explores a beneficial use of depleted uranium as metal shielding in casks designed to contain canisters of vitrified high-level waste. Two high-level waste storage, transport, and disposal shielded cask systems are analyzed. The first system employs a shielded storage and disposal cask having a separate reusable transportation overpack. The second system employs a shielded combined storage, transport, and disposal cask. Conceptual cask designs that hold 1, 3, 4 and 7 high-level waste canisters are described for both systems. In all cases, cask design feasibility was established and analyses indicate that these casks meet applicable thermal, structural, shielding, and contact-handled requirements. Depleted uranium metal casting, fabrication, environmental, and radiation compatibility considerations are discussed and found to pose no serious implementation problems. About one-fourth of the depleted uranium inventory would be used to produce the casks required to store and dispose of the nearly 15,400 high-level waste canisters that would be produced. This study estimates the total-system cost for the preferred 7-canister storage and disposal configuration having a separate transportation overpack would be $6.3 billion. When credits are taken for depleted uranium disposal cost, a cost that would be avoided if depleted uranium were used as cask shielding material rather than disposed of as waste, total system net costs are between $3.8 billion and $5.5 billion.

Yoshimura, H.R.; Ludwigsen, J.S.; McAllaster, M.E. [and others

1996-09-01T23:59:59.000Z

380

3D thermal-electrochemical lithium-ion battery computational modeling.  

E-Print Network (OSTI)

??The thesis presents a modeling framework for simulating three dimensional effects in lithium-ion batteries. This is particularly important for understanding the performance of large scale… (more)

Gerver, Rachel Ellen

2010-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "thermal depletion model" 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

Computational Model For Transient And Steady State Analysis Of A 1-dimensional Auto-thermal Reformer.  

E-Print Network (OSTI)

??Kim, Daejong This study presents a 1-dimensional mathematical model of steam reformer to be used with high temperature solid oxide fuel cell (SOFC). Steam reforming… (more)

Honavara-Prasad, Srikanth

2011-01-01T23:59:59.000Z

382

Disposition of DOE Excess Depleted Uranium, Natural Uranium, and  

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

Disposition of DOE Excess Depleted Uranium, Natural Uranium, and Disposition of DOE Excess Depleted Uranium, Natural Uranium, and Low-Enriched Uranium Disposition of DOE Excess Depleted Uranium, Natural Uranium, and Low-Enriched Uranium The U.S. Department of Energy (DOE) owns and manages an inventory of depleted uranium (DU), natural uranium (NU), and low-enriched uranium (LEU) that is currently stored in large cylinders as depleted uranium hexafluoride (DUF6), natural uranium hexafluoride (NUF6), and low-enriched uranium hexafluoride (LEUF6) at the DOE Paducah site in western Kentucky (DOE Paducah) and the DOE Portsmouth site near Piketon in south-central Ohio (DOE Portsmouth)1. This inventory exceeds DOE's current and projected energy and defense program needs. On March 11, 2008, the Secretary of Energy issued a policy statement (the

383

Testing of and model development for double-walled thermal tubular  

SciTech Connect

Insulated tubular products have become essential for use in steam injection projects. In a steam injection project, steam is created at the surface by either steam boilers or generators. During this process, steam travels from a boiler through surface lines to the wellhead, down the wellbore to the sandface, and into the reservoir. For some projects to be an economic success, cost must be reduced and oil recoveries must be increased by reducing heat losses in the wellbore. With reduced heats losses, steam generation costs are lowered and higher quality steam can be injected into the formation. To address this need, work under this project consisted of the design and construction of a thermal flow loop, testing a double-walled tubular product that was manufactured by Inter-Mountain Pipe Company, and the development and verification of a thermal hydraulic numerical simulator for steam injection. Four different experimental configurations of the double-walled pipe were tested. These configurations included: (1) bare pipe case, (2) bare pipe case with an applied annular vacuum, (3) insulated annular pipe case, and (4) insulated annular pipe case with an applied annular vacuum. Both the pipe body and coupling were tested with each configuration. The results of the experimental tests showed that the Inter-Mountain Pipe Company double-walled pipe body achieved a 98 percent reduction in heat loss when insulation was applied to the annular portion of the pipe. The application of insulation to the annular portion of the coupling reduced the heat losses by only 6 percent. In tests that specified the use of a vacuum in the annular portion of the pipe, leaks were detected and the vacuum could not be held.

Satchwell, R.M.; Johnson, L.A. Jr.

1992-08-01T23:59:59.000Z

384

Effects of Radiation on Thermal Transport and Fuel Performance  

Science Conference Proceedings (OSTI)

Mar 14, 2012 ... A 3D finite element model with microstructure information is created by serial sectioning of a depleted uranium oxide sample using Electron ...

385

Synthetic liquid fuels development: assessment of critical factors. Volume III. Coal resource depletion  

DOE Green Energy (OSTI)

While US coal resources are known to be vast, their rate of depletion in a future based predominantly on coal has not been examined analytically heretofore. The Coal Depletion Model inventories the coal resource on a regional basis and calculates the cost of coal extraction by three technologies - strip and underground mining and in-situ combustion. A plausible coal demand scenario extending from 1975 to the year 2050 is used as a basis in applying the model. In the year 2050, plants in operation include 285 syncrude plants, each producing 100,000 B/D; 312 SNG plants, each producing 250 million SCF/D and 722 coal-fired electric power plants, each of 1000 MW capacity. In addition, there is 890 million tons per year of industrial coal consumption. Such a high level of coal use would deplete US coal resources much more rapidly than most people appreciate. Of course, the actual amount of US coal is unknown, and if the coal in the hypothetical reliability category is included, depletion is delayed. Coal in this category, however, has not been mapped; it is only presumed to exist on the basis of geological theory. The coal resource depletion model shows that unilateral imposition of a severance tax by a state tends to shift production to other coal producing regions. Boom and bust cycles are both delayed and reduced in their magnitude. When several states simultaneously impose severance taxes, the effect of each is weakened.Key policy issues that emerge from this analysis concern the need to reduce the uncertainty of the magnitude and geographic distribution of the US coal resource and the need to stimulate interaction among the parties at interest to work out equitable and acceptable coal conversion plant location strategies capable of coping with the challenges of a high-coal future.

Dickson, E.M.; Yabroff, I.W.; Kroll, C.A.; White, R.K.; Walton, B.L.; Ivory, M.E.; Fullen, R.E.; Weisbecker, L.W.; Hays, R.L.

1977-01-01T23:59:59.000Z

386

Regulation of new depleted uranium uses.  

DOE Green Energy (OSTI)

This report evaluates how the existing U.S. Nuclear Regulatory Commission (NRC) regulatory structure and pending modifications would affect full deployment into radiologically uncontrolled areas of certain new depleted uranium (DU) uses being studied as part of the U.S. Department of Energy's DU uses research and development program. Such new DU uses include as catalysts (for destroying volatile organic compounds in off-gases from industrial processes and for hydrodesulfurization [HDS] of petroleum fuels), semiconductors (for fabricating integrated circuits, solar cells, or thermoelectric devices, especially if such articles are expected to have service in hostile environments), and electrodes (for service in solid oxide fuel cells, in photoelectrochemical cells used to produce hydrogen, and in batteries). The report describes each new DU use and provides a detailed analysis of whether any existing NRC licensing exemption or general license would be available to users of products and devices manufactured to deploy the new use. Although one existing licensing exemption was found to be possibly available for catalysts used for HDS of petroleum fuels and one general license was found to be possibly available for catalysts, semiconductors, and electrodes used in hydrogen production or batteries, existing regulations would require most users of products and devices deploying new DU uses to obtain specific source material licenses from the NRC or an Agreement State. This situation would not be improved by pending regulatory modifications. Thus, deployment of new DU uses may be limited because persons having no previous experience with NRC or Agreement State regulations may be hesitant to incur the costs and inconvenience of regulatory compliance, unless using a DU-containing product or device offers a substantial economic benefit over nonradioactive alternatives. Accordingly, estimating the risk of deploying new DU-containing products and devices in certain radiologically uncontrolled areas is recommended. If the estimated risks of such deployment are found to be acceptable, then it may be possible to justify adding new exemptions or general licenses to the NRC regulations.

Ranek, N. L.

2003-01-22T23:59:59.000Z

387

A phenomenological model of the thermal hydraulics of convective boiling during the quenching of hot rod bundles  

SciTech Connect

In this paper, a phenomenological model of the thermal hydraulics of convective boiling in the post-critical-heat-flux (post-CHF) regime is developed and discussed. The model was implemented in the TRAC-PF1/MOD2 computer code (an advanced best-estimate computer program written for the analysis of pressurized water reactor systems). The model was built around the determination of flow regimes downstream of the quench front. The regimes were determined from the flow-regime map suggested by Ishii and his coworkers. Heat transfer in the transition boiling region was formulated as a position-dependent model. The propagation of the CHF point was strongly dependent on the length of the transition boiling region. Wall-to-fluid film boiling heat transfer was considered to consist of two components: first, a wall-to-vapor convective heat-transfer portion and, second, a wall-to-liquid heat transfer representing near-wall effects. Each contribution was considered separately in each of the inverted annular flow (IAF) regimes. The interfacial heat transfer was also formulated as flow-regime dependent. The interfacial drag coefficient model upstream of the CHF point was considered to be similar to flow through a roughened pipe. A free-stream contribution was calculated using Ishii's bubbly flow model for either fully developed subcooled or saturated nucleate boiling. For the drag in the smooth IAF region, a simple smooth-tube correlation for the interfacial friction factor was used. The drag coefficient for the rough-wavy IAF was formulated in the same way as for the smooth IAF model except that the roughness parameter was assumed to be proportional to liquid droplet diameter entrained from the wavy interface. The drag coefficient in the highly dispersed flow regime considered the combined effects of the liquid droplets within the channel and a liquid film on wet unheated walls. 431 refs., 6 figs., 4 tabs.

Nelson, R.A.; Unal, C.

1991-01-01T23:59:59.000Z

388

Modeling shear failure and permeability enhancement due to coupled Thermal-Hydrological-Mechanical processes in Enhanced Geothermal Reservoirs  

Science Conference Proceedings (OSTI)

The connectivity and accessible surface area of flowing fractures, whether natural or man-made, is possibly the single most important factor, after temperature, which determines the feasibility of an Enhanced Geothermal System (EGS). Rock deformation and in-situ stress changes induced by injected fluids can lead to shear failure on preexisting fractures which can generate microseismic events, and also enhance the permeability and accessible surface area of the geothermal formation. Hence, the ability to accurately model the coupled thermal-hydrologic-mechanical (THM) processes in fractured geological formations is critical in effective EGS reservoir development and management strategies. The locations of the microseismic events can serve as indicators of the zones of enhanced permeability, thus providing vital information for verification of the coupled THM models. We will describe a general purpose computational code, FEHM, developed for this purpose, that models coupled THM processes during multiphase fluid flow and transport in fractured porous media. The code incorporates several models of fracture aperture and stress behavior combined with permeability relationships. We provide field scale examples of applications to geothermal systems to demonstrate the utility of the method.

Kelkar, Sharad [Los Alamos National Laboratory

2011-01-01T23:59:59.000Z

389

Treatment of electronic waste to recover metal values using thermal plasma coupled with acid leaching - A response surface modeling approach  

Science Conference Proceedings (OSTI)

Highlights: Black-Right-Pointing-Pointer Sentences/phrases were modified. Black-Right-Pointing-Pointer Necessary discussions for different figures were included. Black-Right-Pointing-Pointer More discussion have been included on the flue gas analysis. Black-Right-Pointing-Pointer Queries to both the reviewers have been given. - Abstract: The global crisis of the hazardous electronic waste (E-waste) is on the rise due to increasing usage and disposal of electronic devices. A process was developed to treat E-waste in an environmentally benign process. The process consisted of thermal plasma treatment followed by recovery of metal values through mineral acid leaching. In the thermal process, the E-waste was melted to recover the metal values as a metallic mixture. The metallic mixture was subjected to acid leaching in presence of depolarizer. The leached liquor mainly contained copper as the other elements like Al and Fe were mostly in alloy form as per the XRD and phase diagram studies. Response surface model was used to optimize the conditions for leaching. More than 90% leaching efficiency at room temperature was observed for Cu, Ni and Co with HCl as the solvent, whereas Fe and Al showed less than 40% efficiency.

Rath, Swagat S., E-mail: swagat.rath@gmail.com [Institute of Minerals and Materials Technology (CSIR), Bhubaneswar 751 013, Odisha (India); Nayak, Pradeep; Mukherjee, P.S.; Roy Chaudhury, G.; Mishra, B.K. [Institute of Minerals and Materials Technology (CSIR), Bhubaneswar 751 013, Odisha (India)

2012-03-15T23:59:59.000Z

390

Modeling Studies of Eddies in the Leeuwin Current: The Role of Thermal Forcing  

Science Conference Proceedings (OSTI)

A high resolution, multilevel, primitive equation (PE) model is used to investigate the generation and stability of the Leeuwin Current and eddies off the west coast of Australia. Two numerical experiments are conducted to investigate the roles ...

Mary L. Batteen; Martin J. Rutherford

1990-09-01T23:59:59.000Z

391

Critical Simulation Based Evaluation of Thermally Activated Building Systems (TABS) Design Models  

E-Print Network (OSTI)

Building index YOC Climate zone Use and loads Envelope CAin California CZ03 climate zone. The design models wereinvestigated the California climate zones CZ03, CZ04, CZ05,

Basu, Chandrayee

2012-01-01T23:59:59.000Z

392

The Quasi-Linear Equilibration of a Thermally Maintained, Stochastically Excited Jet in a Quasigeostrophic Model  

Science Conference Proceedings (OSTI)

A theory for quasigeostrophic turbulence in baroclinic jets is examined in which interaction between the mean flow and the perturbations is explicitly modeled by the nonnormal operator obtained by linearization about the mean flow, while the eddy–...

Timothy Delsole; Brian F. Farrell

1996-07-01T23:59:59.000Z

393

LINSOL: a model for predicting the optical performance of parabolic trough solar thermal systems  

DOE Green Energy (OSTI)

A detailed model has been developed to predict the optical performance of parabolic trough solar energy systems. The model is one to two orders of magnitude faster than previous, less complete calculations and makes tractable investigation of a wide range of design and application alternatives for trough systems. Representative results are presented that show the dependence of the trough optical performance on field orientation and site latitude.

Dellin, T.A.

1981-01-01T23:59:59.000Z

394

Theoretical Modeling and Experimental Investigation of the Thermal Performance of the LHC Prototype Lattice Cryostats  

E-Print Network (OSTI)

This thesis presents the thermal performance of the LHC (Large Hadron Collider) prototype cryostats both in steady-state and in transient conditions. LHC will be built in the 27 km LEP tunnel and will provide proton-proton collisions. It will make use of superconducting magnets operating in static bath of superfluid helium at 1.9 K. The thesis is mainly divided in three parts. The first part cont ains three chapters which present a brief overview of the LHC project. Part 1-Chapter 1 gives a short introduction to the LHC design layout and performance. Part 1-Chapter 2 refers to LHC cryogenic s ystem and describes the general architecture of the cryogenic plants, the temperature levels and the heat loads. The 50 m long LHC prototype half-cell contains one twin-bore quadrupole and four twin-a perture dipoles. In Part 1-Chapter 3 the design and construction of the prototype dipole and quadrupole cryostats are presented. The LHC prototype cryostats have integrated cryogenic lines, while the final LHC cryostats hav...

Riddone, G

1997-01-01T23:59:59.000Z

395

Application of Distribution Transformer Thermal Life Models to Electrified Vehicle Charging Loads Using Monte-Carlo Method: Preprint  

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

Application of Distribution Application of Distribution Transformer Thermal Life Models to Electrified Vehicle Charging Loads Using Monte-Carlo Method Preprint Michael Kuss, Tony Markel, and William Kramer Presented at the 25th World Battery, Hybrid and Fuel Cell Electric Vehicle Symposium & Exhibition Shenzhen, China November 5 - 9, 2010 Conference Paper NREL/CP-5400-48827 January 2011 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.

396

Assisted thermal stripping (ATS) for removal of PCBs from contaminated soils. Design of experiments modeling of the ATS process  

Science Conference Proceedings (OSTI)

In a companion report, the Assisted Thermal Stripping (ATS) process for enhanced removal of PCBs from PCB-contaminated soil is described. In studies directed toward achieving residual PCB levels of {le}2 ppm, it was found that four factors were particularly important -- (1) process temperature; (2) process time; (3) the amount of additive (for enhancing the removal of PCBs); and (4) steam flow rate. In order to optimize the ATS process, it was deemed crucial to ascertain the relative effect exerted by each of those process factors and the reproducibility of the process. To accomplish that, we have relied on the technique {open_quotes}Design of Experiments{close_quotes} (DOE) to mathematically model the ATS process. After considering the findings from our previous investigations, it was decided to employ formic acid as the additive for enhancing the removal of PCBs.

Krabbenhoft, H.O.; Webb, J.L.; Gascoyne, D.G. [GE Corporate Research & Development, Schenectady, NY (United States); Cawse, J.N. [GE Plastics, Pittsfield, MA (United States)

1996-12-31T23:59:59.000Z

397

Verification of a Depletion Method in SCALE for the Advanced High Temperature Reactor  

SciTech Connect

This study describes a new method utilizing the Dancoff factor to model a non-standard TRISO fuel form characteristic of the AHTR reactor design concept for depletion analysis using the TRITON sequence of SCALE and the validation of this method by code-to-code comparisons. The fuel used in AHTR has the TRISO particles concentrated along the edges of a slab fuel element. This particular geometry prevented the use of a standard DOUBLEHET treatment, previously developed in SCALE to handle NGNP-designed fuel. The new method permits fuel depletion on complicated geometries that traditionally can be handled only by continuous energy based depletion code systems. The method was initially tested on a fuel design typical of the NGNP, where the DOUBLEHET treatment is available. A more comprehensive study was performed using the VESTA code that uses the continuous energy MCNP5 code as a transport solver and ORIGEN2.2 code for depletion calculations. Comparisons of the results indicate good agreement of whole core characteristics, such as the multiplication factor, and the isotopics, including their spatial distribution. Key isotopes analyzed included 235U, 239Pu, 240Pu and 241Pu. The results from this study indicate that the Dancoff factor method can generate estimates of core characteristics with reasonable precision for scoping studies of configurations where the DOUBLEHET treatment is unavailable.

KELLY, RYAN [Texas A& M University; Ilas, Dan [ORNL

2012-01-01T23:59:59.000Z

398

Challenges dealing with depleted uranium in Germany - Reuse or disposal  

SciTech Connect

During enrichment large amounts of depleted Uranium are produced. In Germany every year 2.800 tons of depleted uranium are generated. In Germany depleted uranium is not classified as radioactive waste but a resource for further enrichment. Therefore since 1996 depleted Uranium is sent to ROSATOM in Russia. However it still has to be dealt with the second generation of depleted Uranium. To evaluate the alternative actions in case a solution has to be found in Germany, several studies have been initiated by the Federal Ministry of the Environment. The work that has been carried out evaluated various possibilities to deal with depleted uranium. The international studies on this field and the situation in Germany have been analyzed. In case no further enrichment is planned the depleted uranium has to be stored. In the enrichment process UF{sub 6} is generated. It is an international consensus that for storage it should be converted to U{sub 3}O{sub 8}. The necessary technique is well established. If the depleted Uranium would have to be characterized as radioactive waste, a final disposal would become necessary. For the planned Konrad repository - a repository for non heat generating radioactive waste - the amount of Uranium is limited by the licensing authority. The existing license would not allow the final disposal of large amounts of depleted Uranium in the Konrad repository. The potential effect on the safety case has not been roughly analyzed. As a result it may be necessary to think about alternatives. Several possibilities for the use of depleted uranium in the industry have been identified. Studies indicate that the properties of Uranium would make it useful in some industrial fields. Nevertheless many practical and legal questions are open. One further option may be the use as shielding e.g. in casks for transport or disposal. Possible techniques for using depleted Uranium as shielding are the use of the metallic Uranium as well as the inclusion in concrete. Another possibility could be the use of depleted uranium for the blending of High enriched Uranium (HEU) or with Plutonium to MOX-elements. (authors)

Moeller, Kai D. [Federal Office for Radiation Protection, Bundesamt fuer Strahlenschutz - BFS, Postfach 10 01 49, D-38201 Salzgitter (Germany)

2007-07-01T23:59:59.000Z

399

Assessment of the mechanical performance of the Westinghouse BWR control rod CR 99 at high depletion levels  

SciTech Connect

A long-term program assessing the mechanical performance of the Westinghouse BWR control rod CR 99 at high depletion levels has been performed. The scope of the program has mainly been based on the operation of four CR 99 Generation 2 control rods in demanding positions during 6 and 7 cycles in the Leibstadt Nuclear Power Plant (KKL) and on the detailed visual inspections and blade wing thickness measurements that were performed after the rods were discharged. By correlating statistically the blade wing thickness measurements to the appearance of irradiation-assisted stress corrosion cracking (IASCC), the probability of IASCC appearance as function of the blade wing swelling was estimated. In order to correlate the IASCC probability of a CR 99 to its depletion, the {sup 10}B depletion of the studied rods was calculated in detail on a local level with the stochastic Monte Carlo code MCNP in combination with the Westinghouse nodal code system PHOENIX4/POLCA7. Using this information coupled to the blade wing measurement data, a finite element model describing the blade wing swelling of an arbitrary CR 99 design as function of {sup 10}B depletion could then be generated. In the final step, these relationships were used to quantify the probability of IASCC appearance as function of the {sup 10}B depletion of the CR 99 Generations 2 and 3. Applying this detailed mapping of the CR 99 behavior at high depletion levels and using an on-line core monitoring system with explicit {sup 10}B depletion tracking capabilities will enable a reliable prediction of the probability for IASCC appearance, thus enhancing the optimized design and the sound operation of the CR 99 control rod. Another important outcome of the program was that it was clearly shown that no significant amount of boron leakage did occur through any of the detected IASCC cracks, despite the very high depletion levels achieved. (authors)

Seltborg, P.; Jinnestrand, M. [Westinghouse Electric Sweden AB, SE-721 63 Vaesteraas (Sweden)

2012-07-01T23:59:59.000Z

400

Proceedings of ASHRAE-DOE-BTECC Conference on Building Thermal Envelopes Simplified Modeling for  

E-Print Network (OSTI)

in the envelopes of residential buildings is the primary mechanism to pro- vide ventilation to those buildings. For radon the same mechanisms that drive the ven- tilation, drive the radon entry from soil gas. This paper leakage, air flow, energy conservation, energy calculation, environment, health, modeling. #12

Note: This page contains sample records for the topic "thermal depletion model" 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

Delayed neutron measurements for Th-232, Np-237, Pu-239, Pu-241 and depleted uranium  

E-Print Network (OSTI)

The neutron emission rates from five very pure actinide samples (Th-232, Np-237, Pu-239, Pu-241 and depleted uranium) were measured following equilibrium irradiation in fast and thermal neutron fluxes. The relative abundances (alphas) for the first four groups were calculated from the delayed neutron emission (counts vs. time) data using Keepin's 6-group decay constants (lambdas) for Th-232, Pu-239 and depleted uranium (both fast and thermal neutron induced fissions). The relative abundances (alphas) for the first five groups were calculated for the fast neutron induced fission of Np-237 using the 7-group lambdas obtained by Charlton (1997). The relative abundances for the first five groups were also calculated using the 7-group lambdas proposed by Loaiza and Haskin (2000), the 8-group lambdas proposed by Campbell and Spriggs (1998) and the 8-group lambdas proposed by Piksaikin (2000) for all of the samples (fast neutron induced fission only for Th-232 and Np-237, fast and thermal neutron induced fission for the remainder). Fission product yield and delayed neutron emission probability data from the ENDF-349 and JEF 2.2 nuclear data libraries were also used to simulate neutron emission data from the samples. The calculated neutron yield curves were used to obtain group relative abundances for each of the five actinide samples (fast neutron induced fission only for Th-232 and Np-237, fast and thermal neutron induced fission for the remainder) based on each set of proposed lambdas. The relative abundances obtained from the experiments and calculations are compared and the differences are noted and discussed.

Stone, Joseph C.

2001-01-01T23:59:59.000Z

402

Thermal and Corona Models of Overhead Transmission Lines Operating at High Temperatures  

Science Conference Proceedings (OSTI)

In an attempt to meet increasing demand by pushing more power through existing lines, the power industry has frequently resorted to operating overhead transmission lines at higher temperatures than ever before. There is reason to believe that the empirical models developed in the past for determining conductor temperature and corona performance are in error at these elevated temperatures. In an effort to safely and reliably push more power, it will be important for utilities to understand the temperature...

2007-12-11T23:59:59.000Z

403

Depleted Uranium Dioxide as SNF Waste Package Fill: A Disposal...  

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

DEPLETED URANIUM DIOXIDE AS SNF WASTE PACKAGE FILL: A DISPOSAL OPTION Charles W. Forsberg Oak Ridge National Laboratory * P.O. Box 2008 Oak Ridge, Tennessee 37831-6179 Tel: (865)...

404

DOE Selects Contractor for Depleted Hexafluoride Conversion Project Support  

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

DOE Selects Contractor for Depleted Hexafluoride Conversion Project DOE Selects Contractor for Depleted Hexafluoride Conversion Project Support DOE Selects Contractor for Depleted Hexafluoride Conversion Project Support March 25, 2013 - 12:00pm Addthis Media Contact Bill Taylor, 803-952-8564 Bill.Taylor@srs.gov Cincinnati - The U.S. Department of Energy (DOE) today awarded a competitive small business task order to Navarro Research and Engineering Inc. of Oak Ridge, Tennessee. The award is a $22 million, time and materials task order with a three-year performance period and two one-year extension options. Navarro Research and Engineering Inc. will provide engineering and operations technical support services to the DOE Portsmouth Paducah Project Office (PPPO) in Lexington, Kentucky and the Depleted Uranium Hexafluoride (DUF6) Conversion Project in Paducah, Kentucky and Portsmouth, Ohio.

405

DOE Issues Request for Quotations for Depleted Uranium Hexafluoride  

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

Issues Request for Quotations for Depleted Uranium Hexafluoride Issues Request for Quotations for Depleted Uranium Hexafluoride Conversion Technical Services DOE Issues Request for Quotations for Depleted Uranium Hexafluoride Conversion Technical Services December 12, 2012 - 12:00pm Addthis Media Contact Bill Taylor, 803-952-8564 bill.taylor@srs.gov Cincinnati - The U.S. Department of Energy (DOE) today issued a Request for Quotation (RFQ) for engineering and operations technical services to support the Portsmouth Paducah Project Office and the oversight of operations of the Depleted Uranium Hexafluoride (DUF6) Conversion Project located in Paducah KY, and Portsmouth OH. The RFQ is for a Time-and-Materials Task Order for three years with two one-year option periods. The estimated contract value is approximately $15 - 20 million.

406

DOE Issues Request for Quotations for Depleted Uranium Hexafluoride  

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

Issues Request for Quotations for Depleted Uranium Hexafluoride Issues Request for Quotations for Depleted Uranium Hexafluoride Conversion Technical Services DOE Issues Request for Quotations for Depleted Uranium Hexafluoride Conversion Technical Services December 12, 2012 - 12:00pm Addthis Media Contact Bill Taylor, 803-952-8564 bill.taylor@srs.gov Cincinnati - The U.S. Department of Energy (DOE) today issued a Request for Quotation (RFQ) for engineering and operations technical services to support the Portsmouth Paducah Project Office and the oversight of operations of the Depleted Uranium Hexafluoride (DUF6) Conversion Project located in Paducah KY, and Portsmouth OH. The RFQ is for a Time-and-Materials Task Order for three years with two one-year option periods. The estimated contract value is approximately $15 - 20 million.

407

DOE Selects Contractor for Depleted Hexafluoride Conversion Project Support  

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

Contractor for Depleted Hexafluoride Conversion Project Contractor for Depleted Hexafluoride Conversion Project Support DOE Selects Contractor for Depleted Hexafluoride Conversion Project Support March 25, 2013 - 12:00pm Addthis Media Contact Bill Taylor, 803-952-8564 Bill.Taylor@srs.gov Cincinnati - The U.S. Department of Energy (DOE) today awarded a competitive small business task order to Navarro Research and Engineering Inc. of Oak Ridge, Tennessee. The award is a $22 million, time and materials task order with a three-year performance period and two one-year extension options. Navarro Research and Engineering Inc. will provide engineering and operations technical support services to the DOE Portsmouth Paducah Project Office (PPPO) in Lexington, Kentucky and the Depleted Uranium Hexafluoride (DUF6) Conversion Project in Paducah, Kentucky and Portsmouth, Ohio.

408

Health Risks Associated with Conversion of Depleted UF6  

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

Conversion Conversion DUF6 Health Risks line line Accidents Storage Conversion Manufacturing Disposal Transportation Conversion A discussion of health risks associated with conversion of depleted UF6 to another chemical form. General Health Risks of Conversion The potential environmental impacts, including potential health risks, associated with conversion activities will be evaluated in detail as part of the Depleted Uranium Hexafluoride management program after a contract is awarded for conversion services. This section discusses in general the types of health risks associated with the conversion process. The conversion of depleted UF6 to another chemical form will be done in an industrial facility dedicated to the conversion process. Conversion will involve the handling of depleted UF6 cylinders. Hazardous chemicals, such

409

A Magnetomechanical Thermal Energy Harvester With A Reversible Liquid Interface  

E-Print Network (OSTI)

and Mechanical Model of a Thermal Energy Harvesting Device”,M, and Ferrari V. , “Thermal energy harvesting throughand G. P. Carman, “Thermal energy harvesting device using

He, Hong

2012-01-01T23:59:59.000Z

410

3D Thermal and Electrochemical Model for Spirally Wound Large Format Lithium-ion Batteries (Presentation)  

DOE Green Energy (OSTI)

In many commercial cells, long tabs at both cell sides, leading to uniform potentials along the spiral direction of wound jelly rolls, are rarely seen because of their high manufacturing cost. More often, several metal strips are welded at discrete locations along both current collector foils. With this design, the difference of electrical potentials is easily built up along current collectors in the spiral direction. Hence, the design features of the tabs, such as number, location and size, can be crucial factors for spiral-shaped battery cells. This paper presents a Li-ion battery cell model having a 3-dimensional spiral mesh involving a wound jellyroll structure. Further results and analysis will be given regarding impacts of tab location, number, and size.

Lee, K. J.; Kim, G. H.; Smith, K.

2010-10-14T23:59:59.000Z

411

Production and Handling Slide 38: 48G Depleted UF6 Storage Cylinder  

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

48G Depleted UF6 Storage Cylinder Refer to caption below for image description After enrichment, depleted uranium hexafluoride is placed in large steel cylinders for storage....

412

Thermally-aware modeling and performance evaluation for single-walled carbon nanotube-based interconnects for future high performance integrated circuits  

Science Conference Proceedings (OSTI)

Given the performance and reliability limits of conventional copper interconnects in the tens of nanometer regime, carbon-nanotube (CNT) based interconnects emerge as a potential reliable alternative for future high performance VLSI industry. In this ... Keywords: Carbon nanotube bundles, High performance interconnect, Thermal modeling

Amir Hosseini; Vahid Shabro

2010-10-01T23:59:59.000Z

413

A MATLAB-derived software (geothermMOD1.2) for one-dimensional thermal modeling, and its application to the Corsica-Sardinia batholith  

Science Conference Proceedings (OSTI)

Determination of the thermal state of the crust is of fundamental importance to understand the feedbacks between tectonics, rheology and metamorphism. The most important parameters controlling the variation of temperature with depth in the crust are ... Keywords: Anatexis, Corsica-Sardinia batholith, Geotherms, Numerical modeling, Variscan

Leonardo Casini

2012-08-01T23:59:59.000Z

414

THERMAL RECOVERY  

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

THERMAL RECOVERY Thermal recovery comprises the techniques of steamflooding, cyclic steam stimulation, and in situ combustion. In steamflooding, high-temperature steam is injected...

415

Adjoint-Based Uncertainty Quantification and Sensitivity Analysis for Reactor Depletion Calculations  

E-Print Network (OSTI)

Depletion calculations for nuclear reactors model the dynamic coupling between the material composition and neutron flux and help predict reactor performance and safety characteristics. In order to be trusted as reliable predictive tools and inputs to licensing and operational decisions, the simulations must include an accurate and holistic quantification of errors and uncertainties in its outputs. Uncertainty quantification is a formidable challenge in large, realistic reactor models because of the large number of unknowns and myriad sources of uncertainty and error. We present a framework for performing efficient uncertainty quantification in depletion problems using an adjoint approach, with emphasis on high-fidelity calculations using advanced massively parallel computing architectures. This approach calls for a solution to two systems of equations: (a) the forward, engineering system that models the reactor, and (b) the adjoint system, which is mathematically related to but different from the forward system. We use the solutions of these systems to produce sensitivity and error estimates at a cost that does not grow rapidly with the number of uncertain inputs. We present the framework in a general fashion and apply it to both the source-driven and k-eigenvalue forms of the depletion equations. We describe the implementation and verification of solvers for the forward and ad- joint equations in the PDT code, and we test the algorithms on realistic reactor analysis problems. We demonstrate a new approach for reducing the memory and I/O demands on the host machine, which can be overwhelming for typical adjoint algorithms. Our conclusion is that adjoint depletion calculations using full transport solutions are not only computationally tractable, they are the most attractive option for performing uncertainty quantification on high-fidelity reactor analysis problems.

Stripling, Hayes Franklin

2013-08-01T23:59:59.000Z

416

Radiometric modeling of mechanical draft cooling towers to assist in the extraction of their absolute temperature from remote thermal imagery.  

E-Print Network (OSTI)

??Determination of the internal temperature of a mechanical draft cooling tower (MDCT) from remotely-sensed thermal imagery is important for many applications that provide input to… (more)

Montanaro, Matthew

2009-01-01T23:59:59.000Z

417

Ground surface temperature reconstructions: Using in situ estimates for thermal conductivity acquired with a fiber-optic distributed thermal perturbation sensor  

E-Print Network (OSTI)

with homogeneous thermal properties, to invert cooling data.thermal simulations of DTPS testing showing modeled coolingand cooling. The match between measured and modeled thermal

Freifeld, B.M.

2009-01-01T23:59:59.000Z

418

A semi-analytical model for heat and mass transfer in geothermal reservoirs to estimate fracture surface-are-to-volume ratios and thermal breakthrough using thermally-decaying and diffusing tracers  

SciTech Connect

A semi-analytical model was developed to conduct rapid scoping calculations of responses of thermally degrading and diffusing tracers in multi-well tracer tests in enhanced geothermal systems (EGS). The model is based on an existing Laplace transform inversion model for solute transport in dual-porosity media. The heat- and mass-transfer calculations are decoupled and conducted sequentially, taking advantage of the fact that heat transfer between fractures and the rock matrix is much more rapid than mass transfer and therefore mass transfer will effectively occur in a locally isothermal system (although the system will be nonisothermal along fracture flow pathways, which is accounted for by discretizing the flow pathways into multiple segments that have different temperature histories). The model takes advantage of the analogies between heat and mass transfer, solving the same governing equations with k{sub m}/({rho}C{sub p}){sub w} being substituted for {phi}D{sub m} in the equation for fracture transport and k{sub m}/({rho}C{sub p}){sub m} being subsituted for D{sub m} in the equation for matrix transport; where k = thermal conductivity (cal/cm-s-K), {rho} = density (g/cm{sup 3}), C{sub p} = heat capacity (at constant pressure) (cal/g-K), {phi} = matrix porosity, and D = tracer diffusion coefficient (cm{sup 2}/s), with the subscripts w and m referring to water and matrix, respectively. A significant advantage of the model is that it executes in a fraction of second on a single-CPU personal computer, making it very amenable for parameter estimation algorithms that involve repeated runs to find global minima. The combined thermal-mass transport model was used to evaluate the ability to estimate when thermal breakthrough would occur in a multi-well EGS configuration using thermally degrading tracers. Calculations were conducted to evaluate the range of values of Arrhenius parameters, A and E{sub {alpha}} (pre-exponential factor, 1/s, and activation energy, cal/mol) required to obtain interpretable responses of thermally-degrading tracers that decay according to the rate constant k{sub d} = Ae{sup -E{sub {alpha}}/RT}, where k{sub d} = decay rate constant (1/s), R = ideal gas constant (1.987 cal/mol-K), and T = absolute temperature (K). It is shown that there are relatively narrow ranges of A and E{sub {alpha}} that will result in readily interpretable tracer responses for any given combination of ambient reservoir temperature and working fluid residence time in a reservoir. The combined model was also used to simulate the responses of conservative tracers with different diffusion coefficients as a way of estimating fracture surface-area-to-volume ratios (SA/V) in multi-well EGS systems. This method takes advantage of the fact that the differences in breakthrough curves of tracers with different matrix diffusion coefficients are a function of SA/V. The model accounts for differences in diffusion coefficients as a function of temperature so that tracer responses obtained at different times can be used to obtain consistent estimates of SA/V as the reservoir cools down. Some single-well applications of this approach are simulated with a numerical model to demonstrate the potential to evaluate the effectiveness of EGS stimulations before a second well is drilled.

Reimus, Paul W [Los Alamos National Laboratory

2010-12-08T23:59:59.000Z

419

WINDOW-WALL INTERFACE CORRECTION FACTORS: THERMAL MODELING OF INTEGRATED FENESTRATION AND OPAQUE ENVELOPE SYSTEMS FOR IMPROVED PREDICTION OF ENERGY USE  

Science Conference Proceedings (OSTI)

The boundary conditions for thermal modeling of fenestration systems assume an adiabatic condition between the fenestration system installed and the opaque envelope system. This theoretical adiabatic boundary condition may not be appropriate owing to heat transfer at the interfaces, particularly for aluminum- framed windows affixed to metal- framed walls. In such scenarios, the heat transfer at the interface may increase the discrepancy between real world thermal indices and laboratory measured or calculated indices based on NFRC Rating System.This paper discusses the development of window-wall Interface Correction Factors (ICF) to improve energy impacts of building envelope systems

Bhandari, Mahabir S [ORNL; Ravi, Dr. Srinivasan [University of Florida, Gainesville

2012-01-01T23:59:59.000Z

420

Coal thermolysis modeling: The effect of cross-linking on the thermal decomposition of 1,3-diphenylpropane  

Science Conference Proceedings (OSTI)

In an effort to model the effects of restricted diffusion and cross-linking on the thermal decomposition of polymethylene units linking aromatic moieties in coal, a surface-attached, cross-linked 1,3-diphenylpropane has been synthesized through the condensation of p, p{prime}-HOPh(CH{sub 2}){sub 3}PhOH with a silica surface. Thermolysis of DPP at 375 C has been studied at a variety of surface coverages in which the fraction of diattached DPP varies from ca. 24 to 86% with complete diattachment not yet achieved. The influence of cross-linking and free phenolic functionality (Ph(CH{sub 2}){sub 3}PhOH) on the rate of decomposition and product distribution will be discussed and compared to the thermolysis of Ph(CH{sub 2}){sub 3}Ph as well as fluid phase DPP. Solid state CP/MAS {sup 13}C NMR will be used to prove the chemical composition and motional behavior of the substrate on the surface and their potential mechanistic impact.

Britt, P.F.; Buchanan, A.C. III.; Hagaman, E.W.; Biggs, C.A. (Oak Ridge National Lab., TN (United States))

1990-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "thermal depletion model" 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

Development & experimental validation of a SINDA/FLUINT thermal/fluid/electrical model of a multi-tube AMTEC cell  

Science Conference Proceedings (OSTI)

AMTEC (Alkali Metal Thermal-to-Electric Conversion) cell development has received increased attention and funding in the space power community because of several desirable performance characteristics compared to current radioisotope thermoelectric generation and solar photovoltaic (PV) power generation. AMTEC cell development is critically dependent upon the ability to predict thermal

Terry J. Hendricks; Chris A. Borkowski; Chendong Huang

1998-01-01T23:59:59.000Z

422

Numerical Modeling of the Effects of a Thermal Fence on Pollutant Dispersion in the Stable Atmospheric Boundary Layer  

Science Conference Proceedings (OSTI)

Numerical studies were conducted to evaluate the effects of a line of heating-that is, a thermal fence-on the short-range (less than 1 km from the pollutant source) dispersion of pollutants under various stable nighttime conditions. The thermal ...

Youn-Seo Koo; Danny D. Reible

1996-11-01T23:59:59.000Z

423

MASSIVELY PARALLEL FULLY COUPLED IMPLICIT MODELING OF COUPLED THERMAL-HYDROLOGICAL-MECHANICAL PROCESSES FOR ENHANCED GEOTHERMAL SYSTEM RESERVOIRS  

SciTech Connect

Development of enhanced geothermal systems (EGS) will require creation of a reservoir of sufficient volume to enable commercial-scale heat transfer from the reservoir rocks to the working fluid. A key assumption associated with reservoir creation/stimulation is that sufficient rock volumes can be hydraulically fractured via both tensile and shear failure, and more importantly by reactivation of naturally existing fractures (by shearing) to create the reservoir. The advancement of EGS greatly depends on our understanding of the dynamics of the intimately coupled rock-fracture-fluid system and our ability to reliably predict how reservoirs behave under stimulation and production. In order to increase our understanding of how reservoirs behave under these conditions, we have developed a physics-based rock deformation and fracture propagation simulator by coupling a discrete element model (DEM) for fracturing with a continuum multiphase flow and heat transport model. In DEM simulations, solid rock is represented by a network of discrete elements (often referred as particles) connected by various types of mechanical bonds such as springs, elastic beams or bonds that have more complex properties (such as stress-dependent elastic constants). Fracturing is represented explicitly as broken bonds (microcracks), which form and coalesce into macroscopic fractures when external load is applied. DEM models have been applied to a very wide range of fracturing processes from the molecular scale (where thermal fluctuations play an important role) to scales on the order of 1 km or greater. In this approach, the continuum flow and heat transport equations are solved on an underlying fixed finite element grid with evolving porosity and permeability for each grid cell that depends on the local structure of the discrete element network (such as DEM particle density). The fluid pressure gradient exerts forces on individual elements of the DEM network, which therefore deforms and fractures. Such deformation/fracturing in turn changes the permeability, which again changes the evolution of fluid pressure, coupling the two phenomena. The intimate coupling between fracturing and fluid flow makes the meso-scale DEM simulations necessary, as these methods have substantial advantages over conventional continuum mechanical models of elastic rock deformation. The challenges that must be overcome to simulate EGS reservoir stimulation, preliminary results, progress to date and near future research directions and opportunities will be discussed.

Robert Podgorney; Hai Huang; Derek Gaston

2010-02-01T23:59:59.000Z

424

Depleted uranium as a backfill for nuclear fuel waste package  

DOE Patents (OSTI)

A method is described for packaging spent nuclear fuel for long-term disposal in a geological repository. At least one spent nuclear fuel assembly is first placed in an unsealed waste package and a depleted uranium fill material is added to the waste package. The depleted uranium fill material comprises flowable particles having a size sufficient to substantially fill any voids in and around the assembly and contains isotopically-depleted uranium in the +4 valence state in an amount sufficient to inhibit dissolution of the spent nuclear fuel from the assembly into a surrounding medium and to lessen the potential for nuclear criticality inside the repository in the event of failure of the waste package. Last, the waste package is sealed, thereby substantially reducing the release of radionuclides into the surrounding medium, while simultaneously providing radiation shielding and increased structural integrity of the waste package. 6 figs.

Forsberg, C.W.

1998-11-03T23:59:59.000Z

425

Environmental Risks Associated with Conversion of Depleted UF6  

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

Conversion Conversion Depleted UF6 Environmental Risks line line Storage Conversion Manufacturing Disposal Conversion A general discussion of the potential environmental impacts associated with depleted UF6 conversion activities. Impacts Analyzed in the PEIS The potential environmental impacts associated with conversion activities will be evaluated in detail as part of the Depleted Uranium Hexafluoride management program after a contract is awarded for conversion services. This page discusses in general the types of impacts that might be associated with the conversion process based on the PEIS analysis. The PEIS evaluated the potential environmental impacts for representative conversion facilities. Conversion to uranium oxide and uranium metal were considered. Potential impacts were evaluated for a representative site, and

426

Effect of Shim Arm Depletion in the NBSR  

SciTech Connect

The cadmium shim arms in the NBSR undergo burnup during reactor operation and hence, require periodic replacement. Presently, the shim arms are replaced after every 25 cycles to guarantee they can maintain sufficient shutdown margin. Two prior reports document the expected change in the 113Cd distribution because of the shim arm depletion. One set of calculations was for the present high-enriched uranium fuel and the other for the low-enriched uranium fuel when it was in the COMP7 configuration (7 inch fuel length vs. the present 11 inch length). The depleted 113Cd distributions calculated for these cores were applied to the current design for an equilibrium low-enriched uranium core. This report details the predicted effects, if any, of shim arm depletion on the shim arm worth, the shutdown margin, power distributions and kinetics parameters.

Hanson A. H.; Brown N.; Diamond, D.J.

2013-02-22T23:59:59.000Z

427

Depleted uranium as a backfill for nuclear fuel waste package  

DOE Patents (OSTI)

A method is described for packaging spent nuclear fuel for long-term disposal in a geological repository. At least one spent nuclear fuel assembly is first placed in an unsealed waste package and a depleted uranium fill material is added to the waste package. The depleted uranium fill material comprises flowable particles having a size sufficient to substantially fill any voids in and around the assembly and contains isotonically-depleted uranium in the +4 valence state in an amount sufficient to inhibit dissolution of the spent nuclear fuel from the assembly into a surrounding medium and to lessen the potential for nuclear criticality inside the repository in the event of failure of the waste package. Last, the waste package is sealed, thereby substantially reducing the release of radionuclides into the surrounding medium, while simultaneously providing radiation shielding and increased structural integrity of the waste package.

Forsberg, Charles W.

1997-12-01T23:59:59.000Z

428

Depleted uranium as a backfill for nuclear fuel waste package  

DOE Patents (OSTI)

A method for packaging spent nuclear fuel for long-term disposal in a geological repository. At least one spent nuclear fuel assembly is first placed in an unsealed waste package and a depleted uranium fill material is added to the waste package. The depleted uranium fill material comprises flowable particles having a size sufficient to substantially fill any voids in and around the assembly and contains isotopically-depleted uranium in the +4 valence state in an amount sufficient to inhibit dissolution of the spent nuclear fuel from the assembly into a surrounding medium and to lessen the potential for nuclear criticality inside the repository in the event of failure of the waste package. Last, the waste package is sealed, thereby substantially reducing the release of radionuclides into the surrounding medium, while simultaneously providing radiation shielding and increased structural integrity of the waste package.

Forsberg, Charles W. (Oak Ridge, TN)

1998-01-01T23:59:59.000Z

429

Thermal-Hydraulic Analysis of Advanced Mixed-Oxide Fuel Assemblies with VIPRE-01  

E-Print Network (OSTI)

Two new fuel assembly designs for light water reactors using advanced mixed-oxide fuels have been proposed to reduce the radiotoxicity of used nuclear fuel discharged from nuclear power plants. The research efforts of this thesis are the first to consider the effects of burnup on advanced mixed-oxide fuel assembly performance and thermal safety margin over an assembly?s expected operational burnup lifetime. In order to accomplish this, a new burnup-dependent thermal-hydraulic analysis methodology has been developed. The new methodology models many of the effects of burnup on an assembly design by including burnup-dependent variations in fuel pin relative power from neutronic calculations, assembly power reductions due to fissile content depletion and core reshuffling, and fuel material thermal-physical properties. Additionally, a text-based coupling method is developed to facilitate the exchange of information between the neutronic code DRAGON and thermal-hydraulic code VIPRE-01. The new methodology effectively covers the entire assembly burnup lifetime and evaluates the thermal-hydraulic performance against ANS Condition I, II, and III events with respect to the minimum departure from nucleate boiling ratio, peak cladding temperatures, and fuel centerline temperatures. A comprehensive literature survey on the thermal conductivity of posed fuel materials with burnup-dependence has been carried out to model the advanced materials in the thermal-hydraulic code VIPRE-01. Where documented conductivity values are not available, a simplified method for estimating the thermal conductivity has been developed. The new thermal conductivity models are based on established FRAPCON-3 fuel property models used in the nuclear industry, with small adjustments having been made to account for actinide additions. Steady-state and transient thermal-hydraulic analyses are performed with VIPRE- 01 for a reference UO2 assembly design, and two advanced mixed-oxide fuel assembly designs using the new burnup-dependent thermal-hydraulic analysis methodology. All three designs maintain a sufficiently large thermal margin with respect to the minimum departure from nucleate boiling ratio, and maximum cladding and fuel temperatures during partial and complete loss-of-flow accident scenarios. The presence of a thin (Am,Zr)O2 outer layer on the fuel pellet in the two advanced mixed-oxide fuel assembly designs increases maximum fuel temperatures during transient conditions, but does not otherwise greatly compromise the thermal margin of the new designs.

Bingham, Adam R.

2009-05-01T23:59:59.000Z

430

Radiological Risk Assessment of Capstone Depleted Uranium Aerosols  

SciTech Connect

Assessment of the health risk from exposure to aerosols of depleted uranium (DU) is an important outcome of the Capstone aerosol studies that established exposure ranges to personnel in armored combat vehicles perforated by DU munitions. Although the radiation exposure from DU is low, there is concern that DU deposited in the body may increase cancer rates. Radiation doses to various organs of the body resulting from the inhalation of DU aerosols measured in the Capstone studies were calculated using International Commission on Radiological Protection (ICRP) models. Organs and tissues with the highest calculated committed equivalent 50-yr doses were lung and extrathoracic tissues (nose and nasal passages, pharynx, larynx, mouth and thoracic lymph nodes). Doses to the bone surface and kidney were about 5 to 10% of the doses to the extrathoracic tissues. The methodologies of the ICRP International Steering Committee on Radiation Standards (ISCORS) were used for determining the whole body cancer risk. Organ-specific risks were estimated using ICRP and U.S. Environmental Protection Agency (EPA) methodologies. Risks for crewmembers and first responders were determined for selected scenarios based on the time interval of exposure and for vehicle and armor type. The lung was the organ with the highest cancer mortality risk, accounting for about 97% of the risks summed from all organs. The highest mean lifetime risk for lung cancer for the scenario with the longest exposure time interval (2 h) was 0.42%. This risk is low compared with the natural or background risk of 7.35%. These risks can be significantly reduced by using an existing ventilation system (if operable) and by reducing personnel time in the vehicle immediately after perforation.

Hahn, Fletcher; Roszell, Laurie E.; Daxon, Eric G.; Guilmette, Ray A.; Parkhurst, MaryAnn

2009-02-26T23:59:59.000Z

431

Symposium on Electrochemical and Thermal Modeling of Battery, Fuel Cell, and Photoenergy Conversion Systems, San Diego, CA, Oct. 20-22, 1986, Proceedings  

SciTech Connect

Papers are presented on modeling of the zinc chlorine battery, design modeling of zinc/bromine battery systems, the modeling of aluminum-air battery systems, and a point defect model for a nickel electrode structure. Also considered are the impedance of a tubular electrode under laminar flow, mathematical modeling of a LiAl/Cl2 cell with a gas diffusion Cl2 electrode, ultrahigh power batteries, and battery thermal modeling. Other topics include an Na/beta-alumina/NaAlCl4, Cl2/C circulating cell, leakage currents in electrochemical systems having common electrodes, modeling for CO poisoning of a fuel cell anode, electrochemical corrosion of carbonaceous materials, and electrolyte management in molten carbonate fuel cells.

Selman, J.R.; Maru, H.C.

1986-01-01T23:59:59.000Z

432

Validation of a Monte Carlo based depletion methodology via High Flux Isotope Reactor HEU post-irradiation examination measurements  

Science Conference Proceedings (OSTI)

The purpose of this study is to validate a Monte Carlo based depletion methodology by comparing calculated post-irradiation uranium isotopic compositions in the fuel elements of the High Flux Isotope Reactor (HFIR) core to values measured using uranium mass-spectrographic analysis. Three fuel plates were analyzed: two from the outer fuel element (OFE) and one from the inner fuel element (IFE). Fuel plates O-111-8, O-350-1, and I-417-24 from outer fuel elements 5-O and 21-O and inner fuel element 49-I, respectively, were selected for examination. Fuel elements 5-O, 21-O, and 49-1 were loaded into HFIR during cycles 4, 16, and 35, respectively (mid to late 1960s). Approximately one year after each of these elements were irradiated, they were transferred to the High Radiation Level Examination Laboratory (HRLEL) where samples from these fuel plates were sectioned and examined via uranium mass-spectrographic analysis. The isotopic composition of each of the samples was used to determine the atomic percent of the uranium isotopes. A Monte Carlo based depletion computer program, ALEPH, which couples the MCNP and ORIGEN codes, was utilized to calculate the nuclide inventory at the end-of-cycle (EOC). A current ALEPH/MCNP input for HFIR fuel cycle 400 was modified to replicate cycles 4, 16, and 35. The control element withdrawal curves and flux trap loadings were revised, as well as the radial zone boundaries and nuclide concentrations in the MCNP model. The calculated EOC uranium isotopic compositions for the analyzed plates were found to be in good agreement with measurements, which reveals that ALEPH/MCNP can accurately calculate burn-up dependent uranium isotopic concentrations for the HFIR core. The spatial power distribution in HFIR changes significantly as irradiation time increases due to control element movement. Accurate calculation of the end-of-life uranium isotopic inventory is a good indicator that the power distribution variation as a function of space and time is accurately calculated, i.e. an integral check. Hence, the time dependent heat generation source terms needed for reactor core thermal hydraulic analysis, if derived from this methodology, have been shown to be accurate for highly enriched uranium (HEU) fuel.

Chandler, David [ORNL; Maldonado, G Ivan [ORNL; Primm, Trent [ORNL

2010-01-01T23:59:59.000Z

433

Status Report and Proposal Concerning the Supply of Depleted Uranium Metal Bands for a Particle Detector  

E-Print Network (OSTI)

Status Report and Proposal Concerning the Supply of Depleted Uranium Metal Bands for a Particle Detector

1980-01-01T23:59:59.000Z

434

User manual for AQUASTOR: a computer model for cost analysis of aquifer thermal energy storage coupled with district heating or cooling systems. Volume I. Main text  

DOE Green Energy (OSTI)

A computer model called AQUASTOR was developed for calculating the cost of district heating (cooling) using thermal energy supplied by an aquifer thermal energy storage (ATES) system. The AQUASTOR model can simulate ATES district heating systems using stored hot water or ATES district cooling systems using stored chilled water. AQUASTOR simulates the complete ATES district heating (cooling) system, which consists of two principal parts: the ATES supply system and the district heating (cooling) distribution system. The supply system submodel calculates the life-cycle cost of thermal energy supplied to the distribution system by simulating the technical design and cash flows for the exploration, development, and operation of the ATES supply system. The distribution system submodel calculates the life-cycle cost of heat (chill) delivered by the distribution system to the end-users by simulating the technical design and cash flows for the construction and operation of the distribution system. The model combines the technical characteristics of the supply system and the technical characteristics of the distribution system with financial and tax conditions for the entities operating the two systems into one techno-economic model. This provides the flexibility to individually or collectively evaluate the impact of different economic and technical parameters, assumptions, and uncertainties on the cost of providing district heating (cooling) with an ATES system. This volume contains the main text, including introduction, program description, input data instruction, a description of the output, and Appendix H, which contains the indices for supply input parameters, distribution input parameters, and AQUASTOR subroutines.

Huber, H.D.; Brown, D.R.; Reilly, R.W.

1982-04-01T23:59:59.000Z

435

Influence Of Three Dynamic Predictive Clothing Insulation Models On Building Energy Use, HVAC Sizing And Thermal Comfort  

E-Print Network (OSTI)

ON BUILDING ENERGY USE, HVAC SIZING AND THERMAL COMFORT aThe results showed that when the HVAC is controlled based onequipment sizing. When the HVAC is controlled based on the

Schiavon, Stefano; Lee, Kwang Ho

2013-01-01T23:59:59.000Z

436

Investigation of the MTC noise estimation with a coupled neutronic/thermal-hydraulic dedicated model - 'Closing the loop'  

Science Conference Proceedings (OSTI)

This paper investigates the reliability of different noise estimators aimed at determining the Moderator Temperature Coefficient (MTC) of reactivity in Pressurized Water Reactors. By monitoring the inherent fluctuations in the neutron flux and moderator temperature, an on-line monitoring of the MTC without perturbing reactor operation is possible. In order to get an accurate estimation of the MTC by noise analysis, the point-kinetic component of the neutron noise and the core-averaged moderator temperature noise have to be used. Because of the scarcity of the in-core instrumentation, the determination of these quantities is difficult, and several possibilities thus exist for estimating the MTC by noise analysis. Furthermore, the effect of feedback has to be negligible at the frequency chosen for estimating the MTC in order to get a proper determination of the MTC. By using an integrated neutronic/thermal- hydraulic model specifically developed for estimating the three-dimensional distributions of the fluctuations in neutron flux, moderator properties, and fuel temperature, different approaches for estimating the MTC by noise analysis can be tested individually. It is demonstrated that a reliable MTC estimation can only be provided if the core is equipped with a sufficient number of both neutron detectors and temperature sensors, i.e. if the core contain in-core detectors monitoring both the axial and radial distributions of the fluctuations in neutron flux and moderator temperature. It is further proven that the effect of feedback is negligible for frequencies higher than 0.1 Hz, and thus the MTC noise estimations have to be performed at higher frequencies. (authors)

Demaziere, C.; Larsson, V. [Div. of Nuclear Engineering, Dept. of Applied Physics, Chalmers Univ. of Technology, SE-41296 Gothenburg (Sweden)

2012-07-01T23:59:59.000Z

437

Steam Generator Management Program: Thermal-Hydraulic and Flow-Induced Vibration Analyses of a Representative Model F Steam Generato r  

Science Conference Proceedings (OSTI)

During the Fall 2006 refueling outage of Vogtle 1, circumferential outside-diameter stress corrosion cracking (ODSCC) indications were observed in Model F steam generator tubes on the hot leg near the top of the tubesheet at low-row number, high-column number tubes. Additional ODSCC indications were observed in the same region during the Spring 2008 outage. All tubes with cracklike indications were plugged and stabilized. This report summarizes the comprehensive thermal-hydraulic and flow-induced vibrati...

2009-06-25T23:59:59.000Z

438

Depleted-Uranium Dioxide as SNF Waste Package Particulate Fill...  

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

Thermal Shunt (Replace Convection) Fill Lowers Temperature (Conductivity > Convective Gas Currents) Limited Convective Currents (Tight Geometry) Heat Transfer (Fuel Basket...

439

Influence Of Three Dynamic Predictive Clothing Insulation Models On Building Energy Use, HVAC Sizing And Thermal Comfort  

E-Print Network (OSTI)

CLOTHING INSULATION MODELS ON BUILDING ENERGY USE, HVACClothing Insulation Model; Clothing; Building Energy;clothing insulation models on the building simulation is

Schiavon, Stefano; Lee, Kwang Ho

2013-01-01T23:59:59.000Z

440

Modeling the Thermal Mechanical Behavior of a 300 K Vacuum Vesselthat is Cooled by Liquid Hydrogen in Film Boiling  

DOE Green Energy (OSTI)

This report discusses the results from the rupture of a thin window that is part of a 20-liter liquid hydrogen vessel. This rupture will spill liquid hydrogen onto the walls and bottom of a 300 K cylindrical vacuum vessel. The spilled hydrogen goes into film boiling, which removes the thermal energy from the vacuum vessel wall. This report analyzes the transient heat transfer in the vessel and calculates the thermal deflection and stress that will result from the boiling liquid in contact with the vessel walls. This analysis was applied to aluminum and stainless steel vessels.

Yang, S.Q.; Green, M.A.; Lau, W.

2004-05-07T23:59:59.000Z

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441

User manual for AQUASTOR: a computer model for cost analysis of aquifer thermal-energy storage oupled with district-heating or cooling systems. Volume II. Appendices  

DOE Green Energy (OSTI)

A computer model called AQUASTOR was developed for calculating the cost of district heating (cooling) using thermal energy supplied by an aquifer thermal energy storage (ATES) system. the AQUASTOR Model can simulate ATES district heating systems using stored hot water or ATES district cooling systems using stored chilled water. AQUASTOR simulates the complete ATES district heating (cooling) system, which consists of two prinicpal parts: the ATES supply system and the district heating (cooling) distribution system. The supply system submodel calculates the life-cycle cost of thermal energy supplied to the distribution system by simulating the technical design and cash flows for the exploration, development, and operation of the ATES supply system. The distribution system submodel calculates the life-cycle cost of heat (chill) delivered by the distribution system to the end-users by simulating the technical design and cash flows for the construction and operation of the distribution system. The model combines the technical characteristics of the supply system and the technical characteristics of the distribution system with financial and tax conditions for the entities operating the two systems into one techno-economic model. This provides the flexibility to individually or collectively evaluate the impact of different economic and technical parameters, assumptions, and uncertainties on the cost of providing district heating (cooling) with an ATES system. This volume contains all the appendices, including supply and distribution system cost equations and models, descriptions of predefined residential districts, key equations for the cooling degree-hour methodology, a listing of the sample case output, and appendix H, which contains the indices for supply input parameters, distribution input parameters, and AQUASTOR subroutines.

Huber, H.D.; Brown, D.R.; Reilly, R.W.

1982-04-01T23:59:59.000Z

442

Preliminary Thermal Modeling of HI-Storm 100S-218 Version B Storage Modules at Hope Creek Cuclear Power Station ISFSI  

Science Conference Proceedings (OSTI)

As part of the Used Fuel Disposition Campaign of the U. S. Department of Energy, Office of Nuclear Energy (DOE-NE) Fuel Cycle Research and Development, a consortium of national laboratories and industry is performing visual inspections and temperature measurements of selected storage modules at various locations around the United States. This report documents thermal analyses in in support of the inspections at the Hope Creek Nuclear Generating Station ISFSI. This site utilizes the HI-STORM100 vertical storage system developed by Holtec International. This is a vertical storage module design, and the thermal models are being developed using COBRA-SFS (Michener, et al., 1987), a code developed by PNNL for thermal-hydraulic analyses of multi assembly spent fuel storage and transportation systems. This report describes the COBRA-SFS model in detail, and presents pre-inspection predictions of component temperatures and temperature distributions. The final report will include evaluation of inspection results, and if required, additional post-test calculations, with appropriate discussion of results.

Cuta, Judith M.; Adkins, Harold E.

2013-08-30T23:59:59.000Z

443

A phenomenological model of the thermal-hydraulics of convective boiling during the quenching of hot rod bundles: Part 2, Assessment of the model with steady-state and transient post-CHF data  

SciTech Connect

After completing the thermal-hydraulic model developed in a companion paper, we performed assessment calculations of the model using steady-state and transient post-critical heat flux (CHF) data. This paper discusses the results of those calculations. The hot-patch model, in conjunction with the other thermal-hydraulic models, was capable of modeling the Winfrith post-CHF hot-patch experiments. The hot-patch model kept the wall temperatures at the specified levels in the hot-patch regions and did not allow any quench-front propagation from either the bottom or the top of the test section. Among the four Winfrith runs selected to assess the hot-patch model, the average deviation in hot-patch power predictions was 15.4%, indicating reasonable predictions of the amount of energy transferred to the fluid by the hot patch. The interfacial heat-transfer model tended to slightly under-predict the vapor temperatures. The maximum difference between calculated and measured vapor superheats was 20%, with a 10% difference for the remainder of the runs considered. The wall-to-fluid heat transfer was predicted reasonably well, and the predicted wall superheats were in reasonable agreement with measured data with a maximum relative error of less than 13%. The effects of pressure, test section power, and flow rate on the axial variation of tube wall temperature are predicted reasonably well for a large range of operating parameters. A comparison of the predicted and measured local wall. The thermal-hydraulic model in TRAC/PF1-MOD2 was used to predict the axial variation of void fraction as measured in Winfrith post-CHF tests. The predictions for reflood calculations were reasonable. The model correctly predicted the trends in void fraction as a result of the effect of pressure and power, with the effect of pressure being more apparent than that of power. 13 refs.

Unal, C.; Nelson, R.

1991-01-01T23:59:59.000Z

444

A phenomenological model of the thermal-hydraulics of convective boiling during the quenching of hot rod bundles: Part 2, Assessment of the model with steady-state and transient post-CHF data  

SciTech Connect

After completing the thermal-hydraulic model developed in a companion paper, we performed assessment calculations of the model using steady-state and transient post-critical heat flux (CHF) data. This paper discusses the results of those calculations. The hot-patch model, in conjunction with the other thermal-hydraulic models, was capable of modeling the Winfrith post-CHF hot-patch experiments. The hot-patch model kept the wall temperatures at the specified levels in the hot-patch regions and did not allow any quench-front propagation from either the bottom or the top of the test section. Among the four Winfrith runs selected to assess the hot-patch model, the average deviation in hot-patch power predictions was 15.4%, indicating reasonable predictions of the amount of energy transferred to the fluid by the hot patch. The interfacial heat-transfer model tended to slightly under-predict the vapor temperatures. The maximum difference between calculated and measured vapor superheats was 20%, with a 10% difference for the remainder of the runs considered. The wall-to-fluid heat transfer was predicted reasonably well, and the predicted wall superheats were in reasonable agreement with measured data with a maximum relative error of less than 13%. The effects of pressure, test section power, and flow rate on the axial variation of tube wall temperature are predicted reasonably well for a large range of operating parameters. A comparison of the predicted and measured local wall. The thermal-hydraulic model in TRAC/PF1-MOD2 was used to predict the axial variation of void fraction as measured in Winfrith post-CHF tests. The predictions for reflood calculations were reasonable. The model correctly predicted the trends in void fraction as a result of the effect of pressure and power, with the effect of pressure being more apparent than that of power. 13 refs.

Unal, C.; Nelson, R.

1991-12-31T23:59:59.000Z

445

A passive mechanism for thermal stress regulation in micro-machined beam-type structures: Modeling and experiment  

Science Conference Proceedings (OSTI)

In this article, a passive mechanism for thermal stress regulation in micro-bridge structures is proposed. The mechanism is essentially a set of precisely designed parallel chevron beams that replace one of the fixed ends of the micro-bridge. The axial ...

Pezhman A. Hassanpour; Patricia M. Nieva; Amir Khajepour

2012-05-01T23:59:59.000Z

446

Shock induced multi-mode damage in depleted uranium  

SciTech Connect

Recent dynamic damage studies on depleted uranium samples have revealed mixed mode failure mechanisms leading to incipient cracking as well as ductile failure processes. Results show that delamination of inclusions upon compression may provide nucleation sites for damage initiation in the form of crack tip production. However, under tension the material propagates cracks in a mixed shear localization and mode-I ductile tearing and cracking. Cracks tips appear to link up through regions of severe, shear dominated plastic flow. Shock recovery experiments were conducted on a 50 mm single stage light gas gun. Serial metallographic sectioning was conducted on the recovered samples to characterize the bulk response of the sample. Experiments show delaminated inclusions due to uniaxial compression without damage propagation. Further results show the propagation of the damage through tensile loading to the incipient state, illustrating ductile processes coupled with mixed mode-I tensile ductile tearing, shear localization, and mode-I cracking in depleted uranium.

Koller, Darcie D [Los Alamos National Laboratory; Cerreta, Ellen K [Los Alamos National Laboratory; Gray, Ill, George T [Los Alamos National Laboratory

2009-01-01T23:59:59.000Z

447

Cermet Waste Packages Using Depleted Uranium Dioxide and Steel  

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

CERMET WASTE PACKAGES USING DEPLETED URANIUM DIOXIDE AND STEEL CERMET WASTE PACKAGES USING DEPLETED URANIUM DIOXIDE AND STEEL Charles W. Forsberg Oak Ridge National Laboratory * P.O. Box 2008 Oak Ridge, Tennessee 37831-6180 Tel: (865) 574-6783 Fax: (865) 574-9512 Email: forsbergcw@ornl.gov Manuscript Number: 078 File Name: DuCermet.HLWcon01.article.final Article Prepared for 2001 International High-Level Radioactive Waste Management Conference American Nuclear Society Las Vegas, Nevada April 29-May 3, 2001 Limits: 1500 words; 3 figures Actual: 1450 words; 3 figures Session: 3.6 Disposal Container Materials and Designs The submitted manuscript has been authored by a contractor of the U.S. Government under contract DE-AC05-00OR22725. Accordingly, the U.S. Government retains a nonexclusive, royalty-free license to publish or reproduce the published form of this contribution,

448

depleted underground oil shale for the permanent storage of carbon  

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

depleted underground oil shale for the permanent storage of carbon depleted underground oil shale for the permanent storage of carbon dioxide (CO 2 ) generated during the oil shale extraction process. AMSO, which holds a research, development, and demonstration (RD&D) lease from the U.S. Bureau of Land Management for a 160-acre parcel of Federal land in northwest Colorado's oil-shale rich Piceance Basin, will provide technical assistance and oil shale core samples. If AMSO can demonstrate an economically viable and environmentally acceptable extraction process, it retains the right to acquire a 5,120-acre commercial lease. When subject to high temperatures and high pressures, oil shale (a sedimentary rock that is rich in hydrocarbons) can be converted into oil. Through mineralization, the CO 2 could be stored in the shale

449

Depletion-induced structure and dynamics in bimodal colloidal suspensions.  

Science Conference Proceedings (OSTI)

Combined small angle x-ray scattering and x-ray photon correlation spectroscopy studies of moderately concentrated bimodal hard-sphere colloidal suspensions in the fluid phase show that depletion-induced demixing introduces spatially heterogeneous dynamics with two distinct time scales. The adhesive nature, as well as the mobility, of the large particles is determined by the level of interaction within the monomodal domains. This interaction is driven by osmotic forces, which are governed by the relative concentration of the constituents.

Sikorski, M.; Sandy, A. R.; Narayanan, S. (X-Ray Science Division)

2011-05-03T23:59:59.000Z

450

Accounting for Depletion of Oil and Gas Resources in Malaysia  

Science Conference Proceedings (OSTI)

Since oil and gas are non-renewable resources, it is important to identify the extent to which they have been depleted. Such information will contribute to the formulation and evaluation of appropriate sustainable development policies. This paper provides an assessment of the changes in the availability of oil and gas resources in Malaysia by first compiling the physical balance sheet for the period 2000-2007, and then assessing the monetary balance sheets for the said resource by using the Net Present Value method. Our findings show serious reduction in the value of oil reserves from 2001 to 2005, due to changes in crude oil prices, and thereafter the depletion rates decreased. In the context of sustainable development planning, albeit in the weak sustainability sense, it will be important to ascertain if sufficient reinvestments of the estimated resource rents in related or alternative capitals are being attempted by Malaysia. For the study period, the cumulative resource rents were to the tune of RM61 billion. Through a depletion or resource rents policy, the estimated quantum may guide the identification of a reinvestment threshold (after considering needed capital investment for future development of the industry) in light of ensuring the future productive capacity of the economy at the time when the resource is exhausted.

Othman, Jamal, E-mail: jortman@ukm.my; Jafari, Yaghoob, E-mail: yaghoob.jafari@gmail.com [Universiti Kebangsaan Malaysia, Faculty of Economics and Management (Malaysia)

2012-12-15T23:59:59.000Z

451

CO depletion --- An evolutionary tracer for molecular clouds  

E-Print Network (OSTI)

Planck cold clumps are among the most promising objects to investigate the initial conditions of the evolution of molecular clouds. In this work, by combing the dust emission data from the survey of Planck satellite with the molecular data of $^{12}$CO/$^{13}$CO (1-0) lines from observations with the Purple Mountain Observatory (PMO) 14 m telescope, we investigate the CO abundance, CO depletion and CO-to-H$_{2}$ conversion factor of 674 clumps in the early cold cores (ECC) sample. The median and mean values of the CO abundance are 6.2$\\times10^{-5}$ and 9.1$\\times10^{-5}$, respectively. The mean and median of CO depletion factor are 2.8 and 1.4, respectively. The median value of $X_{CO-to-H_{2}}$ for the whole sample is $3.3\\times10^{20}$ cm$^{-2}$K$^{-1}$km$^{-1}$ s. The CO abundance, CO depletion factor and CO-to-H$_{2}$ conversion factor seems to be strongly correlated to other physical parameters (e.g. dust temperature, dust emissivity spectra index and column density). CO gas severely freeze out in colde...

Liu, Tie; Zhang, Huawei

2013-01-01T23:59:59.000Z

452

Integrability vs Quantum Thermalization  

E-Print Network (OSTI)

Non-integrability is often taken as a prerequisite for quantum thermalization. Still, a generally accepted definition of quantum integrability is lacking. With the basis in the driven Rabi model we discuss this careless usage of the term "integrability" in connection to quantum thermalization. The model would be classified as non-integrable according to the most commonly used definitions, for example, the only preserved quantity is the total energy. Despite this fact, a thorough analysis conjectures that the system will not thermalize. Thus, our findings suggest first of all (i) that care should be paid when linking non-integrability with thermalization, and secondly (ii) that the standardly used definitions for quantum integrability are unsatisfactory.

Jonas Larson

2013-04-12T23:59:59.000Z

453

Midtemperature Solar Systems Test Facility predictions for thermal performance based on test data. Alpha Solarco Model 104 solar collector with 0. 125-inch Schott low-iron glass reflector surface  

DOE Green Energy (OSTI)

Thermal performance predictions based on test data are presented for the Alpha Solarco Model 104 solar collector, with 0.125-inch Schott low-iron glass reflector surface, for three output temperatures at five cities in the United States.

Harrison, T.D.

1981-04-01T23:59:59.000Z

454

FAQ 16-How much depleted uranium hexafluoride is stored in the United  

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

How much depleted uranium hexafluoride is stored in the United States? How much