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Design options for low-conductivity window frames

Description: The window industry's commercialization of low-emissivity coatings and low-conductivity gas-filling over the past few years has helped to drastically reduce heat transfer rates through the glazed areas of windows. However, few changes have taken place in the design and construction of window frames and edges, leaving these elements to account for most of the heat transfer through today's state-of-the-art windows. This paper presents design and material requirements for the manufacture of low-co… more
Date: October 1, 1990
Creator: Byars, N. & Arasteh, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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An historical mullite fiber-reinforced ceramic composite: Characterization of the wootz' crucible refractory

Description: Since at least the sixteenth century, the wootz'' ultra-high carbon white cast-iron ingot was produced in India by melting or carburising iron in a crucible. This ingot was forced into sword blades of so-called Damascus steel. The charged crucible was fired in a long (24-hour) single cycle at high temperature (1150-1250{degree}C) in a strongly reducing atmosphere. Raw materials for the refractory vessel are clay and coked'' rice husks. At high temperatures, two phases reinforce the glassy matri… more
Date: October 1, 1990
Creator: Lowe, T.L. (California Univ., Berkeley, CA (USA)); Merk, N. & Thomas, G. (Lawrence Berkeley Lab., CA (USA))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Combustion and heat transfer in porous media

Description: The objective of the present study is to generate fundamental knowledge about heat transfer and combustion in porous radiant burners (PRBs) in order to improve their performance. A theoretical heat transfer and combustion model is developed to study the characteristics of PRBs. The model accounts for non-local thermal equilibrium between the solid and gas phases. The solid is assumed to absorb, emit and scatter radiant energy. Combustion is modeled as a one-step global reaction. It is revealed … more
Date: June 1990
Creator: Sathe, Sanjeev B.; Peck, Robert E. & Tong, Timothy W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

A high-efficiency thermoelectric converter for space applications

Description: This paper presents a concept for using high-temperature superconducting materials in thermoelectric generators (SCTE) to produce electricity at conversion efficiencies approaching 50% of the Carrot efficiency. The SCTE generator is applicable to systems operating in temperature ranges of high-temperature superconducting materials and thus would be a low-grade converter. Operating in cryogenic temperature ranges provides the advantage of inherently increasing the limits of the Carrot efficiency… more
Date: January 1, 1990
Creator: Metzger, J.D. (Westinghouse Savannah River Co., Aiken, SC (United States)) & El-Genk, M.S. (New Mexico Univ., Albuquerque, NM (United States). Inst. for Space Nuclear Power Studies)
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Computational model for optimizing longitudinal fin heat transfer in laminar internal flows

Description: Optimal configurations are identified, based on a numerical model, for fully developed laminar internal flows whose base boundary walls have perpendicular fins extending longitudinally into the fluid. The optimum coolant flow channel, formed between each fin, has an aspect ratio dependent on the coolant to wall thermal conductivity ratio and on the fin to channel width ratio, which is optimally about unity. A base thickness exists which minimizes the base hot-spot temperature, and its value is … more
Date: November 1, 1990
Creator: Landram, C. S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Unifying the controlling mechanisms for the critical heat flux and quenching: The ability of liquid to contact the hot surface

Description: We investigate the hypothesis that the critical heat flux (CHF) occurs when some point on a heated surface reaches a temperature high enough so that liquid can no longer maintain contact at that point, resulting in a gradual but continuous increase in the overall surface temperature. This hypothesis unifies the occurrence of the CHF with the quenching of hot surfaces by relating them to the same concept: the ability of a liquid to contact a hot surface, generally defined as some fraction of liq… more
Date: January 1, 1990
Creator: Unal, C.; Daw, V. & Nelson, R.A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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In situ vitrification melt and confinement hood performance review

Description: This document consolidates and organizes information available concerning in situ vitrification (ISV) melt behavior and confinement hood performance. This information is derived from reports of various scaled ISV tests conducted at the Pacific Northwest Laboratory (PNL), the Oak Ridge National Laboratory (ORNL), and the Idaho National Engineering Laboratory (INEL). The objective of this document is twofold: (1) to serve as a central reference of information concerning the reported melt and conf… more
Date: September 1, 1990
Creator: Stoots, C.M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Geothermal materials project input for conversion technology task

Description: This ongoing laboratory-based high risk/high payoff R and D program has already yielded several durable cost-effective materials of construction for geothermal energy processes. In FY 1991, R and D in the following areas will be performed: (1) development and downhole testing of advanced high-temperature (300{degrees}C) CO{sub 2}-resistant lightweight (1.1 g/cc) well-cementing materials, (2) high-temperature chemical systems for lost-circulation control, (3) thermally conductive scale-resistant… more
Date: August 1, 1990
Creator: Kukacka, L. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Metallic phase-change materials for solar dynamic energy storage systems

Description: Solar (thermal) dynamic power systems for satellites require a heat storage system that is capable of operating the engine during eclipse. The conventional approach to this thermal storage problem is to use the latent heat of fluoride salts, which would melt during insolation and freeze during eclipse. Although candidate fluorides have large heats of fusion per unit mass, their poor thermal conductivity limits the rate at which energy can be transferred to and from the storage device. System pe… more
Date: December 1, 1990
Creator: Lauf, R.J. & Hamby, C. Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

The potential for fuel-target mixing during a fuel melting accident in an SRS fuel assembly

Description: The mechanical work potential during a whole core melting accident in the Savannah River Site production reactors is strongly influenced by the amount of target material mixing with the fuel. This strong fluence on accident progression is the result of the potential for recriticality of the fuel and the possibility of steam explosions with the molten fuel-target material. In this paper an analysis of the temperature and draining history of the fuel film/target wall composite is made on the basi… more
Date: January 1, 1990
Creator: Ellison, P.G. (Westinghouse Savannah River Co., Aiken, SC (USA)); Epstein, M. (Fauske and Associates, Inc., Burr Ridge, IL (USA)) & Coryell, E.W. (EG and G Idaho, Inc., Idaho Falls, ID (USA))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Capabilities for measuring physical and chemical properties of rocks at high pressure

Description: The Experimental Geophysics Group of the Earth Sciences Department at Lawrence Livermore National Laboratory (LLNL) has experimental equipment that measures a variety of physical properties and phase equilibria and kinetics on rocks and minerals at extreme pressures (to 500 GPa) and temperatures (from 10 to 2800 K). These experimental capabilities are described in this report in terms of published results, photographs, and schematic diagrams.
Date: January 1, 1990
Creator: Durham, W.B. (comp.)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

The transport properties of activated carbon fibers

Description: The transport properties of activated isotropic pitch-based carbon fibers with surface area 1000 m{sup 2}/g have been investigated. We report preliminary results on the electrical conductivity, the magnetoresistance, the thermal conductivity and the thermopower of these fibers as a function of temperature. Comparisons are made to transport properties of other disordered carbons. 19 refs., 4 figs.
Date: July 1990
Creator: di Vittorio, S. L.; Dresselhaus, M. S.; Endo, M.; Issi, J.-P. & Piraux, L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Nonoptimal entropy generation by heat transfer in cryogenic domain

Description: The entropy generation caused by heat conduction has been analyzed for physical situations related to cryostats. The situations under consideration are characterized by heat conduction with presence or absence of heat generation and/or heat convection. The existing information regarding the thermodynamic optimal design is compared with more realistic nonoptimal situations. The difference between the optimal and nonoptimal entropy generation has been analyzed from the quantitative point of view.… more
Date: January 1, 1990
Creator: Sekulic, D.P (Novi Sad Univ. (Yugoslavia) Dept. of Mechanical Engineering) & Edeskuty, F.J. (Los Alamos National Lab., NM (USA))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Electrochromic sun control coverings for windows

Description: The 2 billion square meters (m{sup 2}) of building windows in the United States cause a national energy drain almost as large as the energy supply of the Alaskan oil pipeline. Unlike the pipeline, the drain of energy through windows will continue well into the 21st century. A part of this energy drain is due to unwanted sun gain through windows. This is a problem throughout the country in commercial buildings because they generally require air conditioning even in cold climates. New commercial … more
Date: April 1, 1990
Creator: Benson, D K & Tracy, C E
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Comparison of calculations and in situ results for a large, heated test room at the Waste Isolation Pilot Plant (WIPP)

Description: The mission of the Waste Isolation Pilot Plant (WIPP) Project is to develop the technology for safe disposal of the radioactive Transuranic (TRU) waste forms generated by the US defense programs. The WIPP facility has been constructed in the bedded salt deposits of Southeastern New Mexico. In the existing regulatory context, the requirement is to assure that the potential repository isolates the radioactive waste from the accessible environment and mankind. This requirement means, in part, that… more
Date: August 1, 1990
Creator: Munson, D.E. (Sandia National Labs., Albuquerque, NM (USA)); DeVries, K.L. & Callahan, G.D. (RE/SPEC, Inc., Rapid City, SD (USA))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Predicted irradiation behavior of U sub 3 O sub 8 -Al dispersion fuels for production reactor applications

Description: Candidate fuels for the new heavy-water production reactor include uranium/aluminum alloy and U{sub 3}O{sub 8}--Al dispersion fuels. The U{sub 3}O{sub 8}--Al dispersion fuel would make possible higher uranium loadings and would facilitate uranium recycle. Research efforts on U{sub 3}O{sub 8}--Al fuel include in-pile irradiation studies and development of analytical tools to characterize the behavior of dispersion fuels at high-burnup. In this paper the irradiation performance of U{sub 3}O{sub 8… more
Date: January 1, 1990
Creator: Cronenberg, A.W. (Engineering Science and Analysis, Albuquerque, NM (USA)); Rest, J. (Argonne National Lab., IL (USA)); Hyder, M.L.; Morin, J.P. & Peacock, H.B. (Westinghouse Savannah River Co., Aiken, SC (USA))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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High-temperature thermal storage systems for advanced solar receivers materials selections

Description: Advanced space power systems that use solar energy and Brayton or Stirling heat engines require thermal energy storage (TES) systems to operate continuously through periods of shade. The receiver storage units, key elements in both Brayton and Stirling systems, are designed to use the latent heat of fusion of phase-change materials (PCMs). The power systems under current consideration for near-future National Aeronautics and Space Administration space missions require working fluid temperatures… more
Date: September 1, 1990
Creator: Wilson, D. F.; DeVan, J. H. & Howell, M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Modeling the steady-state ISV (in situ vitrification) process: A 3-D finite element analysis of coupled thermal-electric fields

Description: Steady-state modeling considerations for simulating the in situ vitrification (ISV) process are documented based upon the finite element numerical approach. Recommendations regarding boundary condition specifications and mesh discretization are presented. The effects of several parameters on the ISV process response are calculated and the results discussed. The parameters investigated include: (1) electrode depth, (2) ambient temperature, (3) supplied current, (4) electrical conductivity, (5) e… more
Date: September 1, 1990
Creator: Langerman, M.A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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An investigation of using a phase-change material to improve the heat transfer in a small electronic module for an airborne radar application

Description: Finding new and improved means of cooling small electronic packages are of great importance to today's electronic packaging engineer. Thermal absorption through the use of a material which changes phase is an attractive alternative. Taking advantage of the heat capacity of a material's latent heat of fusion is shown to absorb heat away from the electronics, thus decreasing the overall temperature rise of the system. The energy equation is formulated in terms of enthalpy and discretized using a … more
Date: October 1, 1990
Creator: Snyder, K.W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

The effect of compression on the material R-value of fiberglass batt insulation

Description: Fiberglass batt insulations intended for use in buildings are labeled with an R-value and thickness at which the R-value is achieved. In some cases the insulation is installed in such a way that the label thickness is not achieved. The material R-value of fiberglass batts installed at less than full thickness will be less than the full-thickness R-value. Results are presented for values measured in accordance with ASTM C 518 for commercially available fiberglass batts at full thickness and comp… more
Date: January 1, 1990
Creator: Graves, R.S. & Yarbrough, D.W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Three-dimensional modelling and geothermal process simulation

Description: The subsurface geological model or 3-D GIS is constructed from three kinds of objects, which are a lithotope (in boundary representation), a number of fault systems, and volumetric textures (vector fields). The chief task of the model is to yield an estimate of the conductance tensors (fluid permeability and thermal conductivity) throughout an array of voxels. This is input as material properties to a FEHM numerical physical process model. The main task of the FEHM process model is to distingui… more
Date: January 1, 1990
Creator: Burns, K.L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Dynamics of the Anderson model for dilute magnetic alloys: A quantum Monte Carlo and maximum entropy study

Description: In this article we describe the results of a new method for calculating the dynamical properties of the Anderson model. QMC generates data about the Matsubara Green's functions in imaginary time. To obtain dynamical properties, one must analytically continue these data to real time. This is an extremely ill-posed inverse problem similar to the inversion of a Laplace transform from incomplete and noisy data. Our method is a general one, applicable to the calculation of dynamical properties from … more
Date: January 1, 1990
Creator: Silver, R.N.; Gubernatis, J.E.; Sivia, D.S. (Los Alamos National Lab., NM (USA)) & Jarrell, M. (Ohio State Univ., Columbus, OH (USA). Dept. of Physics)
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Complete fluid equations for low-n singular modes in axisymmetric toroidal plasmas

Description: The goal of this work is to develop a complete linear theory of the singular region, including all important dynamical effects. The present phase of the work treats the more collision fluid regime. A later phase will treat the less collisional gyrokinetic regime. This paper concerns the derivation and form of the fluid equations for the singular region of low-n modes. Later work will treat high-n ballooning modes. In addition, the ordering in the present work must be amended before it is applic… more
Date: January 1, 1990
Creator: Glasser, A.H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Melting of foaming batches: Nuclear waste glass

Description: A simple model is presented for the rate of melting of a batch blanket in an electric glassmelting furnace. The melting process is assumed to be jointly controlled by the heat transfer from the pool of molten glass and the batch-to-glass conversion kinetics. Factors affecting the melting rate in the conversion-controlled regime are discussed. Attention is paid to gas evolution from redox reactions in waste glass batches and component accumulation within the blanket. It is suggested that the hig… more
Date: October 1, 1990
Creator: Hrma, P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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