Sample records for thermal insulation radiation

  1. Radiative transfer and thermal performance levels in foam insulation boardstocks

    E-Print Network [OSTI]

    Moreno, John David

    1991-01-01T23:59:59.000Z

    The validity of predictive models for the thermal conductivity of foam insulation is established based on the fundamental geometry of the closed-cell foam. The extinction coefficient is experimentally and theoretically ...

  2. Thermal Insulation Systems

    E-Print Network [OSTI]

    Stanley, T. F.

    1982-01-01T23:59:59.000Z

    Thermal insulation systems are receiving a high degree of attention in view of increasing energy cost. Industrial, commercial and residential energy users are all well aware of energy cost increases and great emphasis is being directed to energy...

  3. Thermal insulated glazing unit

    DOE Patents [OSTI]

    Selkowitz, S.E.; Arasteh, D.K.; Hartmann, J.L.

    1988-04-05T23:59:59.000Z

    An improved insulated glazing unit is provided which can attain about R5 to about R10 thermal performance at the center of the glass while having dimensions about the same as those of a conventional double glazed insulated glazing unit. An outer glazing and inner glazing are sealed to a spacer to form a gas impermeable space. One or more rigid, non-structural glazings are attached to the inside of the spacer to divide the space between the inner and outer glazings to provide insulating gaps between glazings of from about 0.20 inches to about 0.40 inches. One or more glazing surfaces facing each thermal gap are coated with a low emissivity coating. Finally, the thermal gaps are filled with a low conductance gas such as krypton gas. 2 figs.

  4. Thermal insulated glazing unit

    SciTech Connect (OSTI)

    Selkowitz, Stephen E. (Piedmont, CA); Arasteh, Dariush K. (Oakland, CA); Hartmann, John L. (Seattle, WA)

    1991-01-01T23:59:59.000Z

    An improved insulated glazing unit is provided which can attain about R5 to about R10 thermal performance at the center of the glass while having dimensions about the same as those of a conventional double glazed insulated glazing unit. An outer glazing and inner glazing are sealed to a spacer to form a gas impermeable space. One or more rigid, non-structural glazings are attached to the inside of the spacer to divide the space between the inner and outer glazings to provide insulating gaps between glazings of from about 0.20 inches to about 0.40 inches. One or more glazing surfaces facing each thermal gap are coated with a low emissivity coating. Finally, the thermal gaps are filled with a low conductance gas such as krypton gas.

  5. Thermal insulations using vacuum panels

    DOE Patents [OSTI]

    Glicksman, Leon R. (Lynnfield, MA); Burke, Melissa S. (Pittsburgh, PA)

    1991-07-16T23:59:59.000Z

    Thermal insulation vacuum panels are formed of an inner core of compressed low thermal conductivity powders enclosed by a ceramic/glass envelope evaluated to a low pressure.

  6. Peg supported thermal insulation panel

    DOE Patents [OSTI]

    Nowobilski, Jeffert J. (Orchard Park, NY); Owens, William J. (Kenmore, NY)

    1985-01-01T23:59:59.000Z

    A thermal insulation panel which is lightweight, load bearing, accommodates thermal stress, and has excellent high temperature insulation capability comprising high performance insulation between thin metal walls supported by high density, high strength glass pegs made in compliance with specified conditions of time, temperature and pressure.

  7. Peg supported thermal insulation panel

    DOE Patents [OSTI]

    Nowobilski, J.J.; Owens, W.J.

    1985-04-30T23:59:59.000Z

    A thermal insulation panel which is lightweight, load bearing, accommodates thermal stress, and has excellent high temperature insulation capability comprises high performance insulation between thin metal walls supported by high density, high strength glass pegs made in compliance with specified conditions of time, temperature and pressure. 2 figs.

  8. Variable pressure thermal insulating jacket

    DOE Patents [OSTI]

    Nelson, P.A.; Malecha, R.F.; Chilenskas, A.A.

    1994-09-20T23:59:59.000Z

    A device for controlled insulation of a thermal device is disclosed. The device includes a thermal jacket with a closed volume able to be evacuated to form an insulating jacket around the thermal source. A getter material is in communication with the closed volume of the thermal jacket. The getter material can absorb and desorb a control gas to control gas pressure in the volume of the thermal jacket to control thermal conductivity in the thermal jacket. 10 figs.

  9. Thermal conductivity of thermal-battery insulations

    SciTech Connect (OSTI)

    Guidotti, R.A.; Moss, M.

    1995-08-01T23:59:59.000Z

    The thermal conductivities of a variety of insulating materials used in thermal batteries were measured in atmospheres of argon and helium using several techniques. (Helium was used to simulate the hydrogen atmosphere that results when a Li(Si)/FeS{sub 2} thermal battery ages.) The guarded-hot-plate method was used with the Min-K insulation because of its extremely low thermal conductivity. For comparison purposes, the thermal conductivity of the Min-K insulating board was also measured using the hot-probe method. The thermal-comparator method was used for the rigid Fiberfrax board and Fiberfrax paper. The thermal conductivity of the paper was measured under several levels of compression to simulate the conditions of the insulating wrap used on the stack in a thermal battery. The results of preliminary thermal-characterization tests with several silica aerogel materials are also presented.

  10. Electrically insulated MLI and thermal anchor

    SciTech Connect (OSTI)

    Kamiya, Koji; Furukawa, Masato; Murakami, Haruyuki; Kizu, Kaname; Tsuchiya, Katsuhiko; Koidea, Yoshihiko; Yoshida, Kiyoshi [Japan Atomic Energy Agency, 801-1 Mukoyama, Naka, Ibaraki 311-0193 (Japan); Hatakenaka, Ryuta; Miyakita, Takeshi [Japan Aerospace Exploration and Agency, 2-1-1 Sengen, Tsukuba, Ibaraki 305-8505 (Japan)

    2014-01-29T23:59:59.000Z

    The thermal shield of JT-60SA is kept at 80 K and will use the multilayer insulation (MLI) to reduce radiation heat load to the superconducting coils at 4.4 K from the cryostat at 300 K. Due to plasma pulse operation, the MLI is affected by eddy current in toroidal direction. The MLI is designed to suppress the current by electrically insulating every 20 degree in the toroidal direction by covering the MLI with polyimide films. In this paper, two kinds of designs for the MLI system are proposed, focusing on a way to overlap the layers. A boil-off calorimeter method and temperature measurement has been performed to determine the thermal performance of the MLI system. The design of the electrical insulated thermal anchor between the toroidal field (TF) coil and the thermal shield is also explained.

  11. Degradation of Structural Alloys Under Thermal Insulation

    E-Print Network [OSTI]

    McIntyre, D. R.

    1984-01-01T23:59:59.000Z

    Wet thermal insulation may actively degrade steel and stainless steel structures by general corrosion or stress-corrosion cracking. Two different mechanisms of water ingress into insulation are discussed; flooding from external sources...

  12. Degradation of Structural Alloys Under Thermal Insulation 

    E-Print Network [OSTI]

    McIntyre, D. R.

    1984-01-01T23:59:59.000Z

    Wet thermal insulation may actively degrade steel and stainless steel structures by general corrosion or stress-corrosion cracking. Two different mechanisms of water ingress into insulation are discussed; flooding from external sources...

  13. Thermal performance measurements of insulated roof systems

    SciTech Connect (OSTI)

    Courville, G.E.; Childs, K.W.; Walukas, D.J.; Childs, P.W.; Griggs, E.I.

    1985-01-01T23:59:59.000Z

    Oak Ridge National Laboratory has established a Roof Thermal Researcch Apparatus for carrying out thermal and hygric experiments on sections of low-sloped roofs. Test panels are exposed to a controlled temperature interior space and to the prevailing East Tennessee exterior environment. They are well instrumented and all data are stored and aided in the analysis by computer systems. Current experiments include studies of the effect of wet insulation on membrane temperature, thermal storage phenomena in built-up roof insulation, and the effects of varying surface reflectance on roof thermal performance.

  14. Design Tool for Cryogenic Thermal Insulation Systems

    SciTech Connect (OSTI)

    Demko, Jonathan A [ORNL] [ORNL; Fesmire, J. E. [NASA Kennedy Space Center, Kennedy Space Center, Florida] [NASA Kennedy Space Center, Kennedy Space Center, Florida; Augustynowicz, S. D. [Sierra Lobo Inc., Kennedy Space Center, Florida] [Sierra Lobo Inc., Kennedy Space Center, Florida

    2008-01-01T23:59:59.000Z

    Thermal isolation of low-temperature systems from ambient environments is a constant issue faced by practitioners of cryogenics. For energy-efficient systems and processes to be realized, thermal insulation must be considered as an integrated system, not merely an add-on element. A design tool to determine the performance of insulation systems for comparative trade-off studies of different available material options was developed. The approach is to apply thermal analysis to standard shapes (plane walls, cylinders, spheres) that are relatively simple to characterize with a one-dimensional analytical or numerical model. The user describes the system hot and cold boundary geometry and the operating environment. Basic outputs such as heat load and temperature profiles are determined. The user can select from a built-in insulation material database or input user defined materials. Existing information has been combined with the new experimental thermal conductivity data produced by the Cryogenics Test Laboratory for cryogenic and vacuum environments, including high vacuum, soft vacuum, and no vacuum. Materials in the design tool include multilayer insulation, aerogel blankets, aerogel bulk-fill, foams, powders, composites, and other insulation system constructions. A comparison of the design tool to a specific composite thermal insulation system is given.

  15. Nuclear reactor vessel fuel thermal insulating barrier

    DOE Patents [OSTI]

    Keegan, C. Patrick; Scobel, James H.; Wright, Richard F.

    2013-03-19T23:59:59.000Z

    The reactor vessel of a nuclear reactor installation which is suspended from the cold leg nozzles in a reactor cavity is provided with a lower thermal insulating barrier spaced from the reactor vessel that has a hemispherical lower section that increases in volume from the center line of the reactor to the outer extent of the diameter of the thermal insulating barrier and smoothly transitions up the side walls of the vessel. The space between the thermal insulating harrier and the reactor vessel forms a chamber which can be flooded with cooling water through passive valving to directly cool the reactor vessel in the event of a severe accident. The passive inlet valve for the cooling water includes a buoyant door that is normally maintained sealed under its own weight and floats open when the cavity is Hooded. Passively opening steam vents are also provided.

  16. Impact of Thermally Insulated Floors 

    E-Print Network [OSTI]

    Alghimlas, F.; Omar, E. A.

    2004-01-01T23:59:59.000Z

    of insulated floors. It was found that using an R- 10 floors in multi-story apartment buildings greatly reduce both the peak cooling demand as well as the energy consumption by about 15%, whereas only minimal savings (about 4%) were detected in the case...

  17. Thermal-performance study of liquid metal fast breeder reactor insulation

    SciTech Connect (OSTI)

    Shiu, Kelvin K.

    1980-09-01T23:59:59.000Z

    Three types of metallic thermal insulation were investigated analytically and experimentally: multilayer reflective plates, multilayer honeycomb composite, and multilayer screens. Each type was subjected to evacuated and nonevacuated conditions, where thermal measurements were made to determine thermal-physical characteristics. A variation of the separation distance between adjacent reflective plates of multilayer reflective plates and multilayer screen insulation was also experimentally studied to reveal its significance. One configuration of the multilayer screen insulation was further selected to be examined in sodium and sodium oxide environments. The emissivity of Type 304 stainless steel used in comprising the insulation was measured by employing infrared technology. A comprehensive model was developed to describe the different proposed types of thermal insulation. Various modes of heat transfer inherent in each type of insulation were addressed and their relative importance compared. Provision was also made in the model to allow accurate simulation of possible sodium and sodium oxide contamination of the insulation. The thermal-radiation contribution to heat transfer in the temperature range of interest for LMFBR's was found to be moderate, and the suppression of natural convection within the insulation was vital in preserving its insulating properties. Experimental data were compared with the model and other published results. Moreover, the three proposed test samples were assessed and compared under various conditions as viable LMFBR thermal insulations.

  18. Smoldering combustion hazards of thermal insulation materials

    SciTech Connect (OSTI)

    Ohlemiller, T.J.; Rogers, F.E.

    1980-07-01T23:59:59.000Z

    Work on the smolder ignitability in cellulosic insulation and on thermal analytical characterization of the oxidation of this material is presented. Thermal analysis (TGA and DSC) shows that both retarded and unretarded cellulosic insulation oxidizes in two overall stages, both of which are exothermic. The second stage (oxidation of the char left as a residue of the first stage) is much more energetic on a unit mass basis than the first. However, kinetics and a sufficient exothermicity make the first stage responsible for ignition in most realistic circumstances. Existing smolder retardants such as boric acid have their major effect on the kinetics of the second oxidation stage and thus produce only a rather small (20/sup 0/C) increase in smolder ignition temperature. Several simplified analogs of attic insulations have been tested to determine the variability of minimum smolder ignition temperature. These employed planar or tubular constant temperature heat sources in a thermal environment quite similar to a realistic attic application. Go/no-go tests provided the borderline (minimum) ignition temperature for each configuration. The wide range (150/sup 0/C) of minimum ignition temperatures confirmed the predominant dependence of smolder ignition on heat flow geometry. Other factors (bulk density, retardants) produced much less effect on ignitability.

  19. Thermal Insulation Performance in the Process Industries: Facts and Fallacies

    E-Print Network [OSTI]

    Tye, R. P.

    Guarded Hot Box Study on Thermal Performance of Fibrous Insulations Used in Lofts," private com munication. 295 ESL-IE-85-05-54 Proceedings from the Seventh National Industrial Energy Technology Conference, Houston, TX, May 12-15, 1985 ...THERMAL INSULATION PERFORMANCE IN 'mE PROCESS INDUSTRIES: FACTS AND FALLACIES R.P. Tye Dynatech RID Company, Cambridge, MA, U.S.A. ABSTRACT The efficient use of thermal insulation materials and systems for design of cryogenic and elevated...

  20. Nonclassicality of Thermal Radiation

    E-Print Network [OSTI]

    Lars M. Johansen

    2004-02-16T23:59:59.000Z

    It is demonstrated that thermal radiation of small occupation number is strongly nonclassical. This includes most forms of naturally occurring radiation. Nonclassicality can be observed as a negative weak value of a positive observable. It is related to negative values of the Margenau-Hill quasi-probability distribution.

  1. Radiation-controlled dynamic vacuum insulation

    DOE Patents [OSTI]

    Benson, David K. (Golden, CO); Potter, Thomas F. (Denver, CO)

    1995-01-01T23:59:59.000Z

    A compact vacuum insulation panel comprising a chamber enclosed by two sheets of metal, glass-like spaces disposed in the chamber between the sidewalls, and a high-grade vacuum in the chamber that includes apparatus and methods for enabling and disabling, or turning "on" and "off" the thermal insulating capability of the panel. One type of enabling and disabling apparatus and method includes a metal hydride for releasing hydrogen gas into the chamber in response to heat, and a hydrogen grate between the metal hydride and the chamber for selectively preventing and allowing return of the hydrogen gas to the metal hydride. Another type of enabling and disabling apparatus and method includes a variable emissivity coating on the sheets of metal in which the emissivity is controllably variable by heat or electricity. Still another type of enabling and disabling apparatus and method includes metal-to-metal contact devices that can be actuated to establish or break metal-to-metal heat paths or thermal short circuits between the metal sidewalls.

  2. Radiation-controlled dynamic vacuum insulation

    DOE Patents [OSTI]

    Benson, D.K.; Potter, T.F.

    1995-07-18T23:59:59.000Z

    A compact vacuum insulation panel is described comprising a chamber enclosed by two sheets of metal, glass-like spaces disposed in the chamber between the sidewalls, and a high-grade vacuum in the chamber that includes apparatus and methods for enabling and disabling, or turning ``on`` and ``off`` the thermal insulating capability of the panel. One type of enabling and disabling apparatus and method includes a metal hydride for releasing hydrogen gas into the chamber in response to heat, and a hydrogen grate between the metal hydride and the chamber for selectively preventing and allowing return of the hydrogen gas to the metal hydride. Another type of enabling and disabling apparatus and method includes a variable emissivity coating on the sheets of metal in which the emissivity is controllably variable by heat or electricity. Still another type of enabling and disabling apparatus and method includes metal-to-metal contact devices that can be actuated to establish or break metal-to-metal heat paths or thermal short circuits between the metal sidewalls. 25 figs.

  3. Thermal Effects of Moisture in Rigid Insulation Board

    E-Print Network [OSTI]

    Crow, G. W.

    The impact of moisture in rigid roof insulation upon energy consumption is often assumed to be a simple function of the conductance. This paper will show that there are complex interactions between conductance, thermal mass, and climate. The energy...

  4. Thermal Effects of Moisture in Rigid Insulation Board 

    E-Print Network [OSTI]

    Crow, G. W.

    1992-01-01T23:59:59.000Z

    The impact of moisture in rigid roof insulation upon energy consumption is often assumed to be a simple function of the conductance. This paper will show that there are complex interactions between conductance, thermal mass, and climate. The energy...

  5. The use of coated micropowders to reduce radiation heat transfer in foam insulation

    E-Print Network [OSTI]

    Marge, Arlene Lanciani

    1991-01-01T23:59:59.000Z

    Polyurethane foam is the most effective insulation currently available for buildings. Chlorofluorocarbon (CFC) blowing agents, which have low thermal conductivities, contribute highly to the effectiveness of this insulation. ...

  6. Pipeline system insulation: Thermal insulation and corrosion prevention. (Latest citations from the Rubber and Plastics Research Association database). Published Search

    SciTech Connect (OSTI)

    Not Available

    1994-05-01T23:59:59.000Z

    The bibliography contains citations concerning thermal and corrosion insulation of pipeline systems used to transport liquids and gases. Topics include thermal aging of polyurethane used for foam heating pipes, extrusion film pipeline insulation materials and processes, flexible expanded nitrile rubber pipeline insulation with Class 1 fire rating, and underground fiberglass reinforced polyester insulated pipeline systems. Applications in solar heating systems; underground water, oil, and gas pipelines; interior hot and cold water lines under seawater; and chemical plant pipeline system insulation are included. (Contains 250 citations and includes a subject term index and title list.)

  7. Actively driven thermal radiation shield

    DOE Patents [OSTI]

    Madden, Norman W. (Livermore, CA); Cork, Christopher P. (Pleasant Hill, CA); Becker, John A. (Alameda, CA); Knapp, David A. (Livermore, CA)

    2002-01-01T23:59:59.000Z

    A thermal radiation shield for cooled portable gamma-ray spectrometers. The thermal radiation shield is located intermediate the vacuum enclosure and detector enclosure, is actively driven, and is useful in reducing the heat load to mechanical cooler and additionally extends the lifetime of the mechanical cooler. The thermal shield is electrically-powered and is particularly useful for portable solid-state gamma-ray detectors or spectrometers that dramatically reduces the cooling power requirements. For example, the operating shield at 260K (40K below room temperature) will decrease the thermal radiation load to the detector by 50%, which makes possible portable battery operation for a mechanically cooled Ge spectrometer.

  8. Silica powders for powder evacuated thermal insulating panel and method

    DOE Patents [OSTI]

    Harris, M.T.; Basaran, O.A.; Kollie, T.G.; Weaver, F.J.

    1996-01-02T23:59:59.000Z

    A powder evacuated thermal insulating panel using generally spherical and porous silica particles of a median size less than about 100 nanometers in diameter, a pour packing density of about 0.4 to 0.6 g/cm{sup 3} and an external surface area in the range of about 90 to 600 m{sup 2}/g is described. The silica powders are prepared by reacting a tetraalkyl silicate with ammonia and water in an alcohol solvent, distilling the solution after the reaction to remove the ammonia and recover the alcohol. The resulting aqueous slurry was dried, ball-milled, and dried again to provide the silica particles with defined internal and external porosity. The nanometer size and the large external surface area of the silica particles along with the internal and external porosity of the silica particles provide powder evacuated thermal insulating panels with significantly higher R-values than obtainable using previously known silica powders. 2 figs.

  9. Silica powders for powder evacuated thermal insulating panel and method

    DOE Patents [OSTI]

    Harris, Michael T. (Knoxville, TN); Basaran, Osman A. (Oak Ridge, TN); Kollie, Thomas G. (Oak Ridge, TN); Weaver, Fred J. (Knoxville, TN)

    1996-01-01T23:59:59.000Z

    A powder evacuated thermal insulating panel using generally spherical and porous silica particles of a median size less than about 100 nanometers in diameter, a pour packing density of about 0.4 to 0.6 g/cm.sup.3 and an external surface area in the range of about 90 to 600 m.sup.2/ g is described. The silica powders are prepared by reacting a tetraakyl silicate with ammonia and water in an alcohol solvent, distilling the solution after the reaction to remove the ammonia and recover the alcohol. The resulting aqueous slurry was dried, ball-milled, and dried again to provide the silica particles with defined internal and external porosity. The nanometer size and the large external surface area of the silica particles along with the internal and external porosity of the silica particles provide powder evacuated thermal insulating panels with significantly higher R-values than obtainable using previously known silica powders.

  10. Silica powders for powder evacuated thermal insulating panel and method

    DOE Patents [OSTI]

    Harris, Michael T. (Knoxville, TN); Basaran, Osman A. (Oak Ridge, TN); Kollie, Thomas G. (Oak Ridge, TN); Weaver, Fred J. (Knoxville, TN)

    1994-01-01T23:59:59.000Z

    A powder evacuated thermal insulating panel using generally spherical and porous silica particles of a median size less than about 100 nanometers in diameter, a pour packing density of about 0.4 to 0.6 g/cm.sup.3 and an external surface area in the range of about 90 to 600 m.sup.2 /g is described. The silica powders are prepared by reacting a tetraakyl silicate with ammonia and water in an alcohol solvent, distilling the solution after the reaction to remove the ammonia and recover the alcohol. The resulting aqueous slurry was dried, ball-milled, and dried again to provide the silica particles with defined internal and external porosity. The nanometer size and the large external surface area of the silica particles along with the internal and external porosity of the silica particles provide powder evacuated thermal insulating panels with significantly higher R-values than obtainable using previously known silica powders.

  11. Silica powders for powder evacuated thermal insulating panel and method

    DOE Patents [OSTI]

    Harris, Michael T. (Knoxville, TN); Basaran, Osman A. (Oak Ridge, TN); Kollie, Thomas G. (Oak Ridge, TN); Weaver, Fred J. (Knoxville, TN)

    1995-01-01T23:59:59.000Z

    A powder evacuated thermal insulating panel using generally spherical and porous silica particles of a median size less than about 100 nanometers in diameter, a pour packing density of about 0.4 to 0.6 g/cm.sup.3 and an external surface area in the range of about 90 to 600 m.sup.2/ g is described. The silica powders are prepared by reacting a tetraakyl silicate with ammonia and water in an alcohol solvent, distilling the solution after the reaction to remove the ammonia and recover the alcohol. The resulting aqueous slurry was dried, ball-milled, and dried again to provide the silica particles with defined internal and external porosity. The nanometer size and the large external surface area of the silica particles along with the internal and external porosity of the silica particles provide powder evacuated thermal insulating panels with significantly higher R-values than obtainable using previously known silica powders.

  12. Radiative Heat Transfer Analysis of Fibrous Insulation Materials Using the ZonalGEF Method

    E-Print Network [OSTI]

    Yuen, Walter W.

    Radiative Heat Transfer Analysis of Fibrous Insulation Materials Using the Zonal­GEF Method Walter to analyze radiative heat transfer in high porosity insulation materials which have a large scattering for LI900, a material used in the insulation tile for the space shuttle. Comparisons are presented

  13. Energy Efficient Process Heating: Insulation and Thermal Mass Kevin Carpenter and Kelly Kissock

    E-Print Network [OSTI]

    Kissock, Kelly

    1 Energy Efficient Process Heating: Insulation and Thermal Mass Kevin Carpenter and Kelly Kissock/or evaporation. A practical way of reducing heat loss is by insulating or covering the surfaces. This paper presents methods to quantify heat loss and energy savings from insulating hot surfaces and open tanks

  14. Thermal Performance of Exterior Insulation and Finish Systems Containing Vacuum Insulation Panels

    SciTech Connect (OSTI)

    Childs, Kenneth W [ORNL; Stovall, Therese K [ORNL; Biswas, Kaushik [ORNL; Carbary, Lawrence D [Dow Corning Corporation, Midland, MI

    2013-01-01T23:59:59.000Z

    A high-performance wall system is under development to improve wall thermal performance to a level of U-factor of 0.19 W/(m2 K) (R-30 [h ft2 F]/Btu) in a standard wall thickness by incorporating vacuum insulation panels (VIPs) into an exterior insulation finish system (EIFS). Such a system would be applicable to new construction and will offer a solution to more challenging retrofit situations as well. Multiple design options were considered to balance the need to protect theVIPs during construction and building operation, while minimizing heat transfer through the wall system. The results reported here encompass an indepth assessment of potential system performances including thermal modeling, detailed laboratory measurements under controlled conditions on the component, and system levels according to ASTM C518 (ASTM 2010). The results demonstrate the importance of maximizing the VIP coverage over the wall face. The results also reveal the impact of both the design and execution of system details, such as the joints between adjacent VIPs. The test results include an explicit modeled evaluation of the system performance in a clear wall.

  15. Standard Practice for Evaluating Thermal Insulation Materials for Use in Solar Collectors

    E-Print Network [OSTI]

    American Society for Testing and Materials. Philadelphia

    1994-01-01T23:59:59.000Z

    1.1 This practice sets forth a testing methodology for evaluating the properties of thermal insulation materials to be used in solar collectors with concentration ratios of less than 10. Tests are given herein to evaluate the pH, surface burning characteristics, moisture adsorption, water absorption, thermal resistance, linear shrinkage (or expansion), hot surface performance, and accelerated aging. This practice provides a test for surface burning characteristics but does not provide a methodology for determining combustibility performance of thermal insulation materials. 1.2 The tests shall apply to blanket, rigid board, loose-fill, and foam thermal insulation materials used in solar collectors. Other thermal insulation materials shall be tested in accordance with the provisions set forth herein and should not be excluded from consideration. 1.3 The assumption is made that elevated temperature, moisture, and applied stresses are the primary factors contributing to the degradation of thermal insulation mat...

  16. Thermal balance of a wall with PCM-enhanced thermal insulation

    SciTech Connect (OSTI)

    Kosny, Jan [ORNL] [ORNL; Kossecka, Elizabeth [Institute of Fundamental Technological Research, Polish Academy of Sciences] [Institute of Fundamental Technological Research, Polish Academy of Sciences; Williams, Teresa [ORNL] [ORNL

    2010-01-01T23:59:59.000Z

    ABSTRACT: PCM insulation mixtures function as lightweight thermal mass components. It is expected that these types of dynamic insulation systems will contribute to the objective of reducing energy use in buildings. In this paper, dynamic thermal properties of a material in which phase hange occurs are analyzed, using the temperature-dependent specific heat model. Integral formula for the total heat flow in finite time interval, across the surface of a slab of the phase change material, was derived. Simulations have been performed to analyze heat transfer through a light-weight wall assembly with PCM-enhanced insulation, in different external climate thermal conditions. Results of simulations indicate that for cyclic processes, the effect of PCM in an insulation layer results rather in time shifting of the heat flux extreme values than in reduction of the total heat flow. The heat gains maxima, resulting in high cooling loads, are shifted in time by about two hours and reduced about 15% to 30% for not very high external sol-air temperatures.

  17. Thermal Performance Impacts of Center-of-Glass Deflections in Installed Insulating

    E-Print Network [OSTI]

    LBNL-5800E Thermal Performance Impacts of Center-of- Glass Deflections in Installed Insulating Laboratory Windows and Envelope Materials Group Building Technology and Urban Systems Department: temperature difference Thermal Performance Impacts of Center-of-Glass Deflections in Installed Insulating

  18. Apparatus for thermal performance measurements of insulated roof systems

    SciTech Connect (OSTI)

    Courville, G.E.; Childs, K.W.; Walukas, D.J.; Childs, P.W.; Griggs, E.I.

    1984-01-01T23:59:59.000Z

    The US Department of Energy conducted thermal performance measurements on low-slope roofs with a recently developed field test apparatus at Oak Ridge National Laboratory (ORNL). The apparatus accommodates four 4 ft x 8 ft test specimens and includes the measurement capabilities for specimen temperatures, temperature gradients, heat flows and moisture content. A weather station characterizes outdoor weather conditions. Tests underway include (1) validation of a roof surface temperature model developed to study the effects of wet insulation; (2) measurement of temperature distributions and heat transfer in high R-value roofs; and (3) validation of an analysis of the effectiveness of high reflectance surfaces. Preliminary experimental results are presented and correlations between experiment and modeling are discussed.

  19. Thermal resistance of prototypical cellular plastic roof insulations

    SciTech Connect (OSTI)

    McElroy, D.L.; Graves, R.S.; Weaver, F.J.

    1991-01-01T23:59:59.000Z

    A cooperative industry/government project was initiated in 1989 to evaluate the viability of alternative hydrochlorofluorocarbons (HCFCs) as blowing agents in polyisocyanurate (PIR) boardstock for roofing applications. Five sets of PIR boardstock were produced to industry specifications for current roof insulation technology. The boardstock allowed the performance of four alternative blowing agents (HCFC-123, HCFC-14lb, and two blends of HCFC-123 and HCFC-14lb) to compared to CFC-11. Laboratory and field tests show the relative thermal performance of the individual PIR boards. One set of laboratory tests show the thermal conductivity (k) from 0 to 50{degree}C (30 to 120{degree}F) of boards prior to installation and as a function of time after exposure to field conditions in the Roof Thermal Research Apparatus (0, 9, and 15 months). Another set of laboratory tests show k as a function of aging time 24{degree}C (75{degree}F) and 65{degree}C (150{degree}F) for full-thickness, half-thickness, and quarter-thickness specimens. These test results and modeling calculations show the value of thin specimen testing as an accelerated aging procedure. 24 refs., 5 figs., 7 tabs.

  20. Liquid cooled fiber thermal radiation receiver

    DOE Patents [OSTI]

    Butler, B.L.

    1985-03-29T23:59:59.000Z

    A radiation-to-thermal receiver apparatus for collecting radiation and converting it to thermal energy is disclosed. The invention includes a fibrous mat material which captures radiation striking the receiver. Captured radiation is removed from the fibrous mat material by a transparent fluid within which the material is bathed.

  1. Method and apparatus for filling thermal insulating systems

    DOE Patents [OSTI]

    Arasteh, D.K.

    1992-01-14T23:59:59.000Z

    A method for filling insulated glazing units is disclosed. The method utilizes a vacuum chamber in which the insulated glazing units are placed. The insulated glazing units and vacuum chamber are evacuated simultaneously. The units are then refilled with a low conductance gas such as Krypton while the chamber is simultaneously refilled with air. 3 figs.

  2. A new approach to low-conductivity, environmentally acceptable thermal insulation. Final report

    SciTech Connect (OSTI)

    Buckley, B.; Day, J.; Ferrero-Heredia, M.; Shanklin, E.; Varadarajan, G.; Woodruff, L.

    1996-02-01T23:59:59.000Z

    The object of this work was to develop a low-conductivity, economical, environmentally benign insulation. Specific objectives were to develop the following: (1) a very low conductivity use as ``super insulation`` in refrigerators, and (2) a general-purpose insulation for buildings and other applications. The technical goals of this work were to minimize gas phase, solid phase, and radiative conductivity. The novel approach pursued to achieve low gas phase conductivity was to blow foam with a removable gas or vapor, encapsulate the foam panel in a pouch made with a barrier film, and introduce a very low conductivity gas as the insulating gas phase. For super insulation and general-purpose insulation, the gases of choice were xenon and krypton, respectively. To control cost, the gases were present at low pressure, and the insulating panel was encapsulated with an impermeable polymeric film. Solid-phase conductivity was minimized by using low-density, open-cell, polyurethane foam. For super insulation, radiative heat transfer was impeded by placing aluminized Mylar films between relatively transparent 70-mil foam slabs. For general-purpose insulation, it was projected to impede radiative heat transfer by achieving the same very small cell size with open-cell CO{sub 2}-blown foam as is now achieved with closed-cell CO{sub 2}-blown foam.

  3. Development of a simplified thermal analysis procedure for insulating glass units

    E-Print Network [OSTI]

    Klam, Jeremy Wayne

    2009-06-02T23:59:59.000Z

    A percentage of insulating glass (IG) units break each year due to thermally induced perimeter stresses. The glass industry has known about this problem for many years and an ASTM standard has recently been developed for the design of monolithic...

  4. Thermal conductivity measurements of insulators for fusion blankets

    SciTech Connect (OSTI)

    Horn, F.L.; Fillo, J.A.; Powell, J.R.

    1981-01-01T23:59:59.000Z

    Alumina-silica mat (8 lb/ft/sup 3/) varied in thermal conductivity in air and Ar from 0.06 W/m- K at 300/sup 0/C to 0.22 W/m- K at 1000/sup 0/C, but in He it increased to 0.24 W/m- K at 300/sup 0/C and 0.54 W/m- K at 1000/sup 0/C, while in steam it was about midway between these values. The carbon and graphite felts behaved similarly, but the rigid and denser (24 lb/ft/sup 3/) zirconia fiberboard exhibited superior insulating properties: 0.07 W/m- K at 300/sup 0/C and 0.14 W/m- K at 1000/sup 0/C in air and Ar, and 0.13 W/m- K at 300/sup 0/C and 0.17 W/m- K at 1000/sup 0/C in steam, but rising to 0.15 W/m- K at 300/sup 0/C and 0.49 W/m- K at 1000/sup 0/C in He. The lighter zirconia felt (14 lb/ft/sup 3/) in steam at 1000/sup 0/C was thought to be best at 0.23 W/m- K and only 0.40 W/m- K in He at 1000/sup 0/C.

  5. DATE: __________________________ NVLAP LAB CODE: _________________ NVLAP THERMAL INSULATION MATERIALS APPLICATION (REV. 2013-11-13) PAGE 1 OF 8

    E-Print Network [OSTI]

    : _________________ _________________________________________________________________________________________________________________ NVLAP THERMAL INSULATION MATERIALS APPLICATION (REV. 2013-11-13) PAGE 1 OF 8 Test Method Designation Short Title ______ 01/C01 ASTM C739 (Sec. 9) Cellulosic Fiber (Wood-Base) Loose-Fill Thermal Insulation (Corrosiveness) ______ 01/C02 16 CFR-Part 1209.5 Cellulose Insulation Test Procedures for Corrosiveness (Loose

  6. Development of New Generation of Thermally-Enhanced Fiber Glass Insulation

    SciTech Connect (OSTI)

    Kosny, Jan [ORNL; Yarbrough, David W [ORNL; Childs, Phillip W [ORNL; Miller, William A [ORNL; Atchley, Jerald Allen [ORNL; Shrestha, Som S [ORNL

    2010-03-01T23:59:59.000Z

    This report presents experimental and numerical results from thermal performance studies. The purpose of this Cooperative Research and Development Agreement (CRADA) between UT-Battelle, LLC and John s Manville was to design a basic concept of a new generation of thermally-enhanced fiber glass insulation. Different types of Phase Change Materials (PCMs) have been tested as dynamic components in buildings during the last 4 decades. Most historical studies have found that PCMs enhance building energy performance. Some PCM-enhanced building materials, like PCM-gypsum boards or PCM-impregnated concretes have already found their limited applications in different countries. Today, continued improvements in building envelope technologies suggest that throughout Southern and Central U.S. climates, residences may soon be routinely constructed with PCM in order to maximize insulation effectiveness and maintain low heating and cooling loads. The proposed thermally-enhanced fiber glass insulation will maximize this integration by utilizing a highly-efficient building envelope with high-R thermal insulation, active thermal mass and superior air-tightness. Improved thermal resistance will come from modifications in infrared internal characteristics of the fiber glass insulation. Thermal mass effect can be provided by proprietary thermally-active microencapsulated phase change material (PCM). Work carried out at the Oak Ridge National Laboratory (ORNL) on the CRADA is described in this report.

  7. Life-cycle energy costs of thermal insulation

    SciTech Connect (OSTI)

    Chinneck, J.W.; Chandrashekar, M.; Hahn, C.K.G.

    1980-01-01T23:59:59.000Z

    A set of calculations is presented which compare the magnitude of the energy costs of insulation with the heating energy savings over the expected lifetime of a model dwelling. A representative city is examined in each of four different levels of Canadian climatic severity. The energy cost of insulation was found to be insignificant relative to the heating energy savings caused by its use. The proposed minimum insulation standards for Canada were found to be significantly better than the existing standards although not optimum from an energy viewpoint.

  8. Advanced thermal insulation for energy efficient buildings : structural performance of aerogel composite panels

    E-Print Network [OSTI]

    Goutierre, Thomas

    2011-01-01T23:59:59.000Z

    Aerogels are well known as exceptional thermal insulators. Thermal conductivities of 9 to 10 mW/m.K have been achieved at atmospheric pressure, and a moderate vacuum (between 1/3 and 1/10 of an atmosphere) can lower this ...

  9. Thermal radiation from an accretion disk

    E-Print Network [OSTI]

    F. V. Prigara

    2004-01-20T23:59:59.000Z

    An effect of stimulated radiation processes on thermal radiation from an accretion disk is considered. The radial density waves triggering flare emission and producing quasi-periodic oscillations in radiation from an accretion disk are discussed. It is argued that the observational data suggest the existence of the weak laser sources in a two-temperature plasma of an accretion disk.

  10. Measurements of the apparent thermal conductivity of multi-layer insulation between 20 K and 90 K

    SciTech Connect (OSTI)

    Hurd, Joseph A.; Van Sciver, Steven W. [National High Magnetic Field Laboratory Tallahassee, FL 32310 USA and FAMU-FSU College of Engineering, Department of M.E., Tallahassee, FL 32310 (United States)

    2014-01-29T23:59:59.000Z

    NASA has the need to efficiently store cryogenic propellants in space for long periods of time. One method to improve storage efficiency is to use multi-layer insulation (MLI), a technique that minimizes the boiling rate due to radiation heat transfer. Typically, the thermal performance of MLI is determined by measuring the rate of evaporation of liquid nitrogen from a calibrated cryostat. The main limitation with this method is that testing conditions are restricted by the boiling temperature of the LN{sub 2}, which may not match the requirements of the application. The Multi-Layer Insulation Thermal Conductivity Experiment (MIKE) at the National High Magnetic Field Laboratory is capable of measuring the effective thermal conductivity of MLI at variable boundary temperatures. MIKE uses cryo-refrigerators to control boundary temperatures in the calorimeter and a calibrated thermal link to measure the heat load. To make the measurements requested by NASA, MIKE needed to be recalibrated for the 20 K to 90 K range. Also, due to the expectation of a lower heat transfer rate, the heat load support rod material was changed to one with a lower thermal conductivity to ensure the temperature difference seen on the cold rod could be measurable at the estimated heat load. Presented are the alterations to MIKE including calibration data and heat load measurements on new load-bearing MLI supplied by NASA.

  11. Method of preparing thermal insulation for high temperature microwave sintering operations

    DOE Patents [OSTI]

    Holcombe, C.E.; Dykes, N.L.; Morrow, M.S.

    1996-07-16T23:59:59.000Z

    Superior microwave transparent thermal insulations for high temperature microwave sintering operations were prepared. One embodiment of the thermal insulation comprises granules of boron nitride coated with a very thin layer of glassy carbon made by preparing a glassy carbon precursor and blending it with boron nitride powder to form a mixture. The blended mixture is granulated to form a grit which is dried and heated to form the granules of boron nitride coated with a glassy carbon. Alternatively, grains of glassy carbon are coated with boron nitride by blending a mixture of a slurry comprising boron nitride, boric acid binder, and methyl alcohol with glassy carbon grains to form a blended mixture. The blended mixture is dried to form grains of glassy carbon coated with boron nitride. In addition, a physical mixture of boron nitride powder and glassy carbon grains has also been shown to be an excellent thermal insulation material for microwave processing and sintering. 1 fig.

  12. Method of preparing thermal insulation for high temperature microwave sintering operations

    DOE Patents [OSTI]

    Holcombe, Cressie E. (Knoxville, TN); Dykes, Norman L. (Oak Ridge, TN); Morrow, Marvin S. (Kingston, TN)

    1996-01-01T23:59:59.000Z

    Superior microwave transparent thermal insulations for high temperature microwave sintering operations were prepared. One embodiment of the thermal insulation comprises granules of boron nitride coated with a very thin layer of glassy carbon made by preparing a glassy carbon precursor and blending it with boron nitride powder to form a mixture. The blended mixture is granulated to form a grit which is dried and heated to form the granules of boron nitride coated with a glassy carbon. Alternatively, grains of glassy carbon are coated with boron nitride by blending a mixture of a slurry comprising boron nitride, boric acid binder, and methyl alcohol with glassy carbon grains to form a blended mixture. The blended mixture is dried to form grains of glassy carbon coated with boron nitride. In addition, a physical mixture of boron nitride powder and glassy carbon grains has also been shown to be an excellent thermal insulation material for microwave processing and sintering.

  13. Thermal insulation for high temperature microwave sintering operations and method thereof

    DOE Patents [OSTI]

    Holcombe, Cressie E. (Knoxville, TN); Dykes, Norman L. (Oak Ridge, TN); Morrow, Marvin S. (Kingston, TN)

    1995-01-01T23:59:59.000Z

    Superior microwave transparent thermal insulations for high temperature microwave sintering operations were prepared. One embodiment of the thermal insulation comprises granules of boron nitride coated with a very thin layer of glassy carbon made by preparing a glassy carbon precursor and blending it with boron nitride powder to form a mixture. The blended mixture is granulated to form a grit which is dried and heated to form the granules of boron nitride coated with a glassy carbon. Alternatively, grains of glassy carbon are coated with boron nitride by blending a mixture of a slurry comprising boron nitride, boric acid binder, and methyl alcohol with glassy carbon grains to form a blended mixture. The blended mixture is dried to form grains of glassy carbon coated with boron nitride. In addition, a physical mixture of boron nitride powder and glassy carbon grains has also been shown to be an excellent thermal insulation material for microwave processing and sintering.

  14. Thermal insulating barrier and neutron shield providing integrated protection for a nuclear reactor vessel

    DOE Patents [OSTI]

    Schreiber, R.B.; Fero, A.H.; Sejvar, J.

    1997-12-16T23:59:59.000Z

    The reactor vessel of a nuclear reactor installation which is suspended from the cold leg nozzles in a reactor cavity is provided with a lower thermal insulating barrier spaced from the reactor vessel to form a chamber which can be flooded with cooling water through passive valving to directly cool the reactor vessel in the event of a severe accident. The passive valving also includes bistable vents at the upper end of the thermal insulating barrier for releasing steam. A removable, modular neutron shield extending around the upper end of the reactor cavity below the nozzles forms with the upwardly and outwardly tapered transition on the outer surface of the reactor vessel, a labyrinthine channel which reduces neutron streaming while providing a passage for the escape of steam during a severe accident, and for the cooling air which is circulated along the reactor cavity walls outside the thermal insulating barrier during normal operation of the reactor. 8 figs.

  15. Thermal insulation for high temperature microwave sintering operations and method thereof

    DOE Patents [OSTI]

    Holcombe, C.E.; Dykes, N.L.; Morrow, M.S.

    1995-09-12T23:59:59.000Z

    Superior microwave transparent thermal insulations for high temperature microwave sintering operations were prepared. One embodiment of the thermal insulation comprises granules of boron nitride coated with a very thin layer of glassy carbon made by preparing a glassy carbon precursor and blending it with boron nitride powder to form a mixture. The blended mixture is granulated to form a grit which is dried and heated to form the granules of boron nitride coated with a glassy carbon. Alternatively, grains of glassy carbon are coated with boron nitride by blending a mixture of a slurry comprising boron nitride, boric acid binder, and methyl alcohol with glassy carbon grains to form a blended mixture. The blended mixture is dried to form grains of glassy carbon coated with boron nitride. In addition, a physical mixture of boron nitride powder and glassy carbon grains has also been shown to be an excellent thermal insulation material for microwave processing and sintering. 1 fig.

  16. Thermal insulating barrier and neutron shield providing integrated protection for a nuclear reactor vessel

    DOE Patents [OSTI]

    Schreiber, Roger B. (Penn Twp., PA); Fero, Arnold H. (New Kensington, PA); Sejvar, James (Murrysville, PA)

    1997-01-01T23:59:59.000Z

    The reactor vessel of a nuclear reactor installation which is suspended from the cold leg nozzles in a reactor cavity is provided with a lower thermal insulating barrier spaced from the reactor vessel to form a chamber which can be flooded with cooling water through passive valving to directly cool the reactor vessel in the event of a severe accident. The passive valving also includes bistable vents at the upper end of the thermal insulating barrier for releasing steam. A removable, modular neutron shield extending around the upper end of the reactor cavity below the nozzles forms with the upwardly and outwardly tapered transition on the outer surface of the reactor vessel, a labyrinthine channel which reduces neutron streaming while providing a passage for the escape of steam during a severe accident, and for the cooling air which is circulated along the reactor cavity walls outside the thermal insulating barrier during normal operation of the reactor.

  17. Entanglement from thermal black body radiation

    E-Print Network [OSTI]

    Daniel Braun

    2005-09-06T23:59:59.000Z

    Two non--interacting quantum systems which couple to a common environment with many degrees of freedom initially in thermal equilibrium can become entangled due to the indirect interaction mediated through this heat bath. I examine here the dynamics of reservoir induced entanglement for a heat bath consisting of a thermal electro--magnetic radiation field, such as black body radiation or the cosmic microwave background, and show how the effect can be understood as result of an effective induced interaction.

  18. Bell-inequality violation with "thermal" radiation

    E-Print Network [OSTI]

    Radim Filip; Miloslav Dusek; Jaromir Fiurasek; Ladislav Mista

    2001-05-17T23:59:59.000Z

    The model of a quantum-optical device for a conditional preparation of entangled states from input mixed states is presented. It is demonstrated that even thermal or pseudo-thermal radiation can be entangled in such a way, that Bell-inequalities are violated.

  19. Validation of the thermal effect of roof with the Spraying and green plants in an insulated building

    SciTech Connect (OSTI)

    Zhou, Nan; Gao, Weijun; Nishida, Masaru; Ojima, Toshio

    2004-08-08T23:59:59.000Z

    In recent years, roof-spraying and rooftop lawns have proven effective on roofs with poor thermal insulation. However, the roofs of most buildings have insulating material to provide thermal insulation during the winter. The effects of insulation has not previously been quantified. In this study, the authors collected measurements of an insulated building to quantify the thermal effects of roof-spraying and rooftop lawns. Roof-spraying did not significantly reduce cooling loads and required significant amounts of water. The conclusion is that roof spraying is not suitable for buildings with well-insulated roofs. Rooftop lawns, however, significantly stabilized the indoor temperature while additionally helping to mitigate the heat island phenomenon.

  20. Active Thermal Extraction of Near-field Thermal Radiation

    E-Print Network [OSTI]

    Ding, Ding

    2015-01-01T23:59:59.000Z

    Radiative heat transport between materials supporting surface-phonon polaritons is greatly enhanced when the materials are placed at sub-wavelength separation as a result of the contribution of near-field surface modes. However, the enhancement is limited to small separations due to the evanescent decay of the surface waves. In this work, we propose and numerically demonstrate an active scheme to extract these modes to the far-field. Our approach exploits the monochromatic nature of near-field thermal radiation to drive a transition in a laser gain medium, which, when coupled with external optical pumping, allows the resonant surface mode to be emitted into the far-field. Our study demonstrates a new approach to manipulate thermal radiation that could find applications in thermal management.

  1. Thermal Insulating Concrete Wall Panel Design for Sustainable Built Environment

    E-Print Network [OSTI]

    Zhou, Ao

    Air-conditioning system plays a significant role in providing users a thermally comfortable indoor environment, which is a necessity in modern buildings. In order to save the vast energy consumed by air-conditioning system, ...

  2. "Flexible aerogel as a superior thermal insulation for high temperature superconductor cable applications"

    SciTech Connect (OSTI)

    White, Shannon O. [Aspen Aerogel, Inc.; Demko, Jonathan A [ORNL; Tomich, A. [Aspen Aerogel, Inc.

    2010-01-01T23:59:59.000Z

    High temperature superconducting (HTS) cables are an advanced technology that can both strengthen and improve the national electrical distribution infrastructure. HTS cables require sufficient cooling to overcome inherent low temperature heat loading. Heat loads are minimized by the use of cryogenic envelopes or cryostats. Cryostats require improvement in efficiency, reliability, and cost reduction to meet the demanding needs of HTS conductors (1G and 2G wires). Aspen Aerogels has developed a compression resistant aerogel thermal insulation package to replace compression sensitive multi-layer insulation (MLI), the incumbent thermal insulation, in flexible cryostats for HTS cables. Oak Ridge National Laboratory tested a prototype aerogel package in a lab-scale pipe apparatus to measure the rate of heat invasion. The lab-scale pipe test results of the aerogel solution will be presented and directly compared to MLI. A compatibility assessment of the aerogel material with HTS system components will also be presented. The aerogel thermal insulation solution presented will meet the demanding needs of HTS cables.

  3. Modulation and amplification of radiative far field heat transfer : towards a simple radiative thermal transistor

    E-Print Network [OSTI]

    Joulain, Karl; Drevillon, Jeremie; Ben-Abdallah, Philippe

    2015-01-01T23:59:59.000Z

    We show in this article that phase change materials (PCM) exhibiting a phase transition between a dielectric state and a metallic state are good candidates to perform modulation as well as amplification of radiative thermal flux. We propose a simple situation in plane parallel geometry where a so-called radiative thermal transistor could be achieved. In this configuration, we put a PCM between two blackbodies at different temperatures. We show that the transistor effect can be achieved easily when this material has its critical temperature between the two blackbody temperatures. We also see, that the more the material is reflective in the metallic state, the more switching effect is realized whereas the more PCM transition is stiff in temperature, the more thermal amplification is high. We finally take the example of VO2 that exhibits an insulator-metallic transition at 68{\\textdegree}C. We show that a demonstrator of a radiative transistor could easily be achieved in view of the heat flux levels predicted. F...

  4. Polyurethane/polyisocyanurate foam thermal insulation. (Latest citations from the Rubber and Plastics Research Association database). Published Search

    SciTech Connect (OSTI)

    Not Available

    1994-06-01T23:59:59.000Z

    The bibliography contains citations concerning the use of polyisocyanurate/polyurethane foam for thermal insulation building materials. The topics discussed include flammability and smoke generation characteristics, building frame sheathing materials, fiber reinforcement, laminated insulation foam boards, substitution for controversial formaldehyde foams and aging characteristics. Performance evaluations of existing buildings with installed foam insulation are included. (Contains a minimum of 187 citations and includes a subject term index and title list.)

  5. Photodetectors with passive thermal radiation control

    DOE Patents [OSTI]

    Lin, Shawn-Yu (Albuquerque, NM); Fleming, James G. (Albuquerque, NM); Dodson, Brian W. (Albuquerque, NM)

    2001-10-02T23:59:59.000Z

    A new class of photodetectors which include means for passive shielding against undesired thermal radiation is disclosed. Such devices can substitute in applications currently requiring cooled optical sensors, such as IR detection and imaging. This description is included for purposes of searching, and is not intended to limit or otherwise influence the interpretation of the present invention.

  6. Characterization of Min-K TE-1400 Thermal Insulation

    SciTech Connect (OSTI)

    Hemrick, James Gordon [ORNL; Lara-Curzio, Edgar [ORNL; King, James [ORNL

    2008-07-01T23:59:59.000Z

    Min-K 1400TE insulation material was characterized at Oak Ridge National Laboratory for use in structural applications under gradient temperature conditions. Initial compression testing was performed at room temperature at various loading rates ranging between 5 and 500 psi/hour (?35 and 3500 kPa/hour) to determine the effect of sample size and test specimen geometry on the compressive strength of Min-K. To determine the loading rates that would be used for stress relaxation testing, compression tests were next carried out at various levels followed by stress relaxation under constant strain at temperatures of 650, 850, and 900oC. Additional high temperature compression testing was performed with samples loaded at a rate of 53 psi/hour (365 kPa/hour) in three load steps of 50, 100 and 200 psi (345, 690, and 1380 kPa) with quick unload/load cycles between steps and followed by a hold period in load control (3 to 100 hours) to allow for sample creep. Testing was carried out at 190, 382, 813, and 850oC. Isothermal stress relaxation testing was performed at temperatures of 190, 382, 813, and 850oC and initial loads of 100 and 200 psi (690 and 1380 kPa). Gradient stress relaxation testing was intended to be performed at temperatures of 850/450oC and 450/190oC with initial loads of 100 or 200 psi (690 and 1380 kPa) performed under constant strain utilizing a twelve-step loading scheme with loading every half hour at a rate of 5.56% strain/hour.

  7. Plasma-activated direct bonding of diamond-on-insulator wafers to thermal oxide grown silicon wafers

    E-Print Network [OSTI]

    Akin, Tayfun

    microscopy, profilometer and wafer bow measurements. Plasma-activated direct bonding of DOI wafers to thermalPlasma-activated direct bonding of diamond-on-insulator wafers to thermal oxide grown silicon (CMP) on the diamond surface makes a poor bonding to silicon wafers with thermal oxide. Our results

  8. Reduction in the thermal resistance (R-value) of loose-fill insulation and fiberglass batts due to compression

    SciTech Connect (OSTI)

    Yarbrough, D.W.; Wright, J.H.

    1981-04-01T23:59:59.000Z

    A method is presented for calculating the thickness reduction of loose-fill insulations and fiberglass batts that result from compressive forces exerted by additional insulation. The thickness reduction is accompanied by an increase in density and a reduction in the R value of the compressed layer. Calculations for thermal resistance of two layers of insulation are given. Information in 4 appendices includes: identification of products tested (products from 3 companies); experimental values for thickness as a function of loading; Fortran programs and output; and calculated R values for stacked insulations. (MCW)

  9. Sierra Designs 20 degrees F Wild Bill Climashield Sleeping Bag ClimashieldTM HL, a high-loft continuous filament insulation, offers excellent thermal

    E-Print Network [OSTI]

    Walker, Lawrence R.

    -loft continuous filament insulation, offers excellent thermal efficiency, durability and water resistance Chest to create a pillow; no need for a pillow to take up valuable space in your backpack Insulated draft tube

  10. Proceedings of the ninth IEA workshop on radiation effects in ceramic insulators

    SciTech Connect (OSTI)

    Zinkle, S.J.; Burn, G.L. [comps.; Hodgson, E.R.; Shikama, T.

    1997-12-31T23:59:59.000Z

    Several IEA workshops have been held over the past few years to discuss the growing number of experimental studies on the intriguing phenomenon of radiation induced electrical degradation (RIED). In the past year, several new RIED irradiation experiments have been performed which have a significant impact on the understanding of the RIED phenomenon. These experiments include a HFIR neutron irradiation experiment on 12 different grades of single- and poly-crystal alumina (450 C, {approximately}3 dpa, 200 V/mm) and several additional neutron, electron and light ion irradiation experiments. The primary objective of the IEA workshop was to review the available RIED studies on ceramic insulators. Some discussion of recent work in other areas such as loss tangent measurements, mechanical strength, etc. occurred on the final afternoon of the workshop. The IEA workshop was held in conjunction with a US-Japan JUPITER program experimenter`s workshop on dynamic radiation effects in ceramic insulators.

  11. Design and construction of a radiation resistant quadrupole using metal oxide insulated CICC

    SciTech Connect (OSTI)

    Albert F. Zeller

    2012-12-28T23:59:59.000Z

    The construction of a engineering test model of a radiation resistant quadrupole is described. The cold-iron quadrupole uses coils fabricated from metal-oixide (synthetic spinel) insulated Cable-In-Conduit-Conductor (CICC). The superconductor is NbTi in a copper matrix. The quadrupole is designed to produce a pole-tip field of 2 T with an operating current of 7,000 A.

  12. Thermal loading considerations for synchrotron radiation mirrors

    SciTech Connect (OSTI)

    Holdener, F.R.; Berglin, E.J.; Fuchs, B.A.; Humpal, H.H.; Karpenko, V.P.; Martin, R.W.; Tirsell, K.G.

    1986-03-26T23:59:59.000Z

    Grazing incidence mirrors used to focus synchrotron radiation beams through small distant apertures have severe optical requirements. The surface distortion due to heat loading of the first mirror in a bending magnet beam line is of particular concern when a large fraction of the incident beam is absorbed. In this paper we discuss mirror design considerations involved in minimizing the thermal/mechanical loading on vertically deflecting first surface mirrors required for SPEAR synchrotron radiation beam lines. Topics include selection of mirror material and cooling method, the choice of SiC for the substrate, optimization of the thickness, and the design of the mirror holder and cooling mechanism. Results obtained using two-dimensional, finite-element thermal/mechanical distortion analysis are presented for the case of a 6/sup 0/ grazing incidence SiC mirror absorbing up to 260 W at Beam Line VIII on the SPEAR ring. Test descriptions and results are given for the material used to thermally couple this SiC mirror to a water-cooled block. The interface material is limited to applications for which the equivalent normal heat load is less than 20 W/cm/sup 2/.

  13. Roof system effects on in-situ thermal performance of HCFC polyisocyanurate insulation. [Hydrochlorofluorocarbon (HCFC)

    SciTech Connect (OSTI)

    Christian, J.E.; Desjarlais, A.O.; Courville, G.; Graves, R.

    1992-01-01T23:59:59.000Z

    Industry-produced, permeably-faced, experimental polyisocyanurate (PIR) laminated boardstock foamed with several different hydrochlorofluorcarbons (HCFCS) is undergoing in-situ testing at the Building Envelopes Research User Center at Oak Ridge National Laboratory (ORNL). The overall objective of this research is to determine the long term thermal performance differences between PIR foamed with CFC-11 and PIR foamed with HCFC-123, HCFC-14lb and blends of HCFCs. Boards from the same batch were installed in outdoor test facilities and instrumented in part to determine if the insulation thermal performance aging characteristics are dependent on how they are handled and installed in the field. One of the major contributions of this research is the field validation of an accelerated thermal aging procedure. The laboratory measurements of the apparent thermal conductivity (k) of 10-mm-thick slices conducted over a period of less than a year are used to predict the k of 38-50-mm-thick PIR laminated board stock for 12--20 years after production. In situ thermal performance measurements of these well characterized three-year-old boards under white and under black ethylene propylene diene monomer (EPDM) membranes are compared with the accelerated aging procedure and with boards from the same batch in different roofing systems: mechanically attached EPDM, fully adhered EPDM, and built-up roof (BUR). The comparison indicates that this accelerated aging procedure should be seriously considered for providing in-service thermal performance information to building owners and roofing contractors.

  14. Roof system effects on in-situ thermal performance of HCFC polyisocyanurate insulation

    SciTech Connect (OSTI)

    Christian, J.E.; Desjarlais, A.O.; Courville, G.; Graves, R.

    1992-10-01T23:59:59.000Z

    Industry-produced, permeably-faced, experimental polyisocyanurate (PIR) laminated boardstock foamed with several different hydrochlorofluorcarbons (HCFCS) is undergoing in-situ testing at the Building Envelopes Research User Center at Oak Ridge National Laboratory (ORNL). The overall objective of this research is to determine the long term thermal performance differences between PIR foamed with CFC-11 and PIR foamed with HCFC-123, HCFC-14lb and blends of HCFCs. Boards from the same batch were installed in outdoor test facilities and instrumented in part to determine if the insulation thermal performance aging characteristics are dependent on how they are handled and installed in the field. One of the major contributions of this research is the field validation of an accelerated thermal aging procedure. The laboratory measurements of the apparent thermal conductivity (k) of 10-mm-thick slices conducted over a period of less than a year are used to predict the k of 38-50-mm-thick PIR laminated board stock for 12--20 years after production. In situ thermal performance measurements of these well characterized three-year-old boards under white and under black ethylene propylene diene monomer (EPDM) membranes are compared with the accelerated aging procedure and with boards from the same batch in different roofing systems: mechanically attached EPDM, fully adhered EPDM, and built-up roof (BUR). The comparison indicates that this accelerated aging procedure should be seriously considered for providing in-service thermal performance information to building owners and roofing contractors.

  15. Corrosiveness of wet residential building thermal insulation---Mechanisms and evaluation of electrochemical methods for assessing corrosion behavior

    SciTech Connect (OSTI)

    Stansbury, E.E. [Stansbury (E.E.), Knoxville, TN (United States)

    1991-10-01T23:59:59.000Z

    An evaluation has been made of the corrosiveness of selected wet residential building thermal insulation materials in contact with low carbon steel. Investigations were conducted both in wet insulations and in filtered leachates from insulations derived from thirteen cellulosic, three mineral fiber and four foam products. Potentiodynamic polarization measurements are reported from which the overall corrosion response was assessed and then the techniques of Tafel and polarization resistance analysis applied to estimate corrosion rates. Corrosion rates were also estimated electrochemically using a direct reading instrument which performs the rate calculation based on the polarization resistance principle. Direct determinations of corrosion rate were based on weight loss measurements.

  16. Thermal Decomposition of Radiation-Damaged Polystyrene

    SciTech Connect (OSTI)

    Abrefah, John; Klinger, George S.

    2000-09-26T23:59:59.000Z

    The radiation-damaged polystyrene (given the identification name of 'polycube') was fabricated by mixing high-density polystyrene material ("Dylene Fines # 100") with plutonium and uranium oxides. The polycubes were used in the 1960s for criticality studies during processing of spent nuclear fuel. The polycubes have since been stored for almost 40 years at the Hanford Plutonium Finishing Plant (PFP) after failure of two processes to reclaim the plutonium and uranium oxides from the polystyrene matrix. Thermal decomposition products from this highly cross-linked polystyrene matrix were characterized using Gas Chromatograph/Mass Spectroscopy (GC/MS) system coupled to a horizontal furnace. The decomposition studies were performed in air and helium atmospheres at about 773 K. The volatile and semi-volatile organic products for the radiation-damaged polystyrene were different compared to virgin polystyrene. The differences were in the number of organic species generated and their concentrations. In the inert (i.e., helium) atmosphere, the major volatile organic products identified (in order of decreasing concentrations) were styrene, benzene, toluene, ethylbenzene, xylene, nathphalene, propane, .alpha.-methylbenzene, indene and 1,2,3-trimethylbenzene. But in air, the major volatile organic species identified changed slightly. Concentrations of the organic species in the inert atmosphere were significantly higher than those for the air atmosphere processing. Overall, 38 volatile organic species were identified in the inert atmosphere compared to 49 species in air. Twenty of the 38 species in the inert conditions were also products in the air atmosphere. Twenty-two oxidized organic products were identified during thermal processing in air.

  17. Polystyrene foams for thermal insulation. (Latest citations from the Rubber and Plastics Research Asociation database). Published Search

    SciTech Connect (OSTI)

    Not Available

    1994-07-01T23:59:59.000Z

    The bibliography contains citations concerning the use of polystyrene foam as a thermal insulator. References discuss applications in railroad tracks, masonry walls, foundations for shallow buildings, and commercial roofing. Use as a vibration medium is referenced. Topics include designing with foam and self-extinguishing foams. (Contains a minimum of 77 citations and includes a subject term index and title list.)

  18. Thermal performance of typical light frame walls with reflective surface insulations

    SciTech Connect (OSTI)

    Miller, R.G. (Jim Walter Research Corp., St. Petersburg, FL (US)); Riskowski, G.L.; Christianson, L.L. (Agricultural Engineering Dept., Univ. of Illinois at Urbana-Champaign, IL (US))

    1989-01-01T23:59:59.000Z

    A series of tests were conducted in a guarded hotbox to evaluate the thermal performance (R-value) of wall constructions typical of light-frame buildings that are commonly used in agricultural applications. The systems were insulated with either a commercially available foil-faced bubble pack material (FFBP) or foil-faced polyisocyanurate (PIR) foam board. Tests were conducted under two different temperature conditions, chosen to be representative of a midwestern winter and summer. This paper reports temperatures of the surfaces bounding the reflective airspaces measured and the R-value calculated. These data were used in the ASHRAE series/parallel calculations and the resultant R-value was compared to the measured R-value. Agreement was usually better than 10%.

  19. Glass-mica composite: a new structural thermal-insulating material for building applications

    SciTech Connect (OSTI)

    Low, N.M.P.

    1981-12-01T23:59:59.000Z

    Homogeneous, rigid glass-mica composites have been synthesized from mixtures of Canadian natural mica flakes of the phlogopite type and ground glass powders prepared from recycled soda-lime waste glasses by a simple sintering process. By means of selection of compositions and processing techniques, composites can be fabricated into products that exhibit a celular structure, a highly densified structure, and multilayer and sandwich structures. The cellular structure composite has a thermal conductivity in the range of 0.165 to 0.230 W/m /sup 0/C when measured over the temperature range 25 to 180/sup 0/C, and a compressive strength of about 0.874 MPa; the highly densified composite, on the other hand, has a thermal conductivity in the range of 0.155 to 0.330 W/m /sup 0/C, a compressive strength in excess of 40 MPa, and an instantaneous coefficient of thermal expansion of 5.8 X 10/sup -6///sup 0/C at 100/sup 0/C. These glass-mica composites exhibit qualities such as insulating efficiency, safety, mechanical strength, and durability that are suitable for engineering applications in building structures or other systems.

  20. NEUTRON STAR ENVELOPES AND THERMAL RADIATION FROM THE MAGNETIC SURFACE

    E-Print Network [OSTI]

    NEUTRON STAR ENVELOPES AND THERMAL RADIATION FROM THE MAGNETIC SURFACE in: C. Kouveliotou, J. van.Petersburg, Russia Abstract. The thermal structure of neutron star envelopes is discussed with emphasis on analytic on the opacities and the thermal structure is further reviewed in view of the application to pulsar cooling

  1. The Analysis of Dynamic Thermal Performance of Insulated Wall and Building Cooling Energy Consumption in Guangzhou

    E-Print Network [OSTI]

    Zhao, L.; Li, X.; Li, L.; Gao, Y.

    2006-01-01T23:59:59.000Z

    ST. The simulation predictions indicate that reductions in the cooling load and maximum cooling demand are obtained when the insulation is added in the wall, but the potential of energy saving is quite limited when the wall only is insulated....

  2. Experimental Investigation on Thermal Properties of a Steel-jacketed Steam Heating Pipeline with Vacuum Insulation 

    E-Print Network [OSTI]

    Na, W.; Zou, P.

    2006-01-01T23:59:59.000Z

    The steel-jacketed steam heating pipeline employs vacuum insulation to improve the insulating effect and reduce the corrosion, and hence increases the heat transfer efficiency of the heating network and building energy efficiency. It is important...

  3. A COMPARISON OF TWO THERMAL INSULATION AND STRUCTURAL MATERIALS FOR USE IN TYPE B PACKAGINGS

    SciTech Connect (OSTI)

    Blanton, P.; Eberl, K.

    2010-07-16T23:59:59.000Z

    This paper presents the summary of design features and test results of two Type B Shipping Package prototype configurations comprising different insulating materials developed by the Savannah River National Laboratory (SRNL) for the Department of Energy. The materials evaluated, a closed-cell polyurethane foam and a vacuformed ceramic fiber material, were selected to provide adequate structural protection to the package containment vessel during Normal Conditions of Transport (NCT) and Hypothetical Accident Condition (HAC) events and to provide thermal protection during the HAC fire. Polyurethane foam has been used in shipping package designs for many years because of the stiffness it provides to the structure and because of the thermal protection it provides during fire scenarios. This comparison describes how ceramic fiber material offers an alternative to the polyurethane foam in a specific overpack design. Because of the high operating temperature ({approx}2,300 F) of the ceramic material, it allows for contents with higher heat loads to be shipped than is possible with polyurethane foam. Methods of manufacturing and design considerations using the two materials will be addressed.

  4. Survey and evaluation of available thermal insulation materials for use on solar heating and cooling systems

    SciTech Connect (OSTI)

    Not Available

    1980-03-01T23:59:59.000Z

    This is the final report of a survey and evaluation of insulation materials for use with components of solar heating and cooling systems. The survey was performed by mailing questionnaires to manufacturers of insulation materials and by conducting an extensive literature search to obtain data on relevant properties of various types of insulation materials. The study evaluated insulation materials for active and passive solar heating and cooling systems and for multifunction applications. Primary and secondary considerations for selecting insulation materials for various components of solar heating and cooling systems are presented.

  5. Electrically-gated near-field radiative thermal transistor

    E-Print Network [OSTI]

    Yang, Yue

    2015-01-01T23:59:59.000Z

    In this work, we propose a near-field radiative thermal transistor made of two graphene-covered silicon carbide (SiC) plates separated by a nanometer vacuum gap. Thick SiC plates serve as the thermal "source" and "drain", while graphene sheets function as the "gate" to modulate the near-field photon tunneling by tuning chemical potential with applied voltage biases symmetrically or asymmetrically. The radiative heat flux calculated from fluctuational electrodynamics significantly varies with graphene chemical potentials, which can tune the coupling between graphene plasmon across the vacuum gap. Thermal modulation, switching, and amplification, which are the key features required for a thermal transistor, are theoretically realized and analyzed. This work will pave the way to active thermal management, thermal circuits, and thermal computing.

  6. Effect of gaps on the performance of the vertically installed wet thermal insulator

    SciTech Connect (OSTI)

    Kim, S. H.; Kim, Y. I.; Park, C. T.; Choi, S.; Yoon, J. [Korea Atomic Energy Research Inst., Daeduk-daero 989-111, Yuseong-Gu, Daejeon, 305-353 (Korea, Republic of)

    2012-07-01T23:59:59.000Z

    In SMART, the main flow path of the reactor coolant and the pressurizer partially share common walls in the reactor coolant system. To reduce this heat transfer, the wet thermal insulator (WTI) is installed on the inner wall of the pressurizer. The WTI is constituted of stacked thin stainless steel plates. The water layer width between the plates is chosen to suppress natural convection in each layer. The plates of the WTI require clearance for thermal expansion. When the WTI is installed on a vertical wall, this clearance might cause gaps at the top and bottom at the operating condition. In this study, we focused on the effect of gaps at the both ends on the WTI performance. A numerical simulation was conducted for an 8-layer WTI with gaps at the both ends. To compare with this, a simulation of a WTI without a gap, which is an ideal case, was also conducted. The simulation was conducted in a 2-dimensional manner by a commercial computational fluid dynamics code, FLUENT. The simulations showed that the WTI thermal performance was substantially decreased by a flow that circulated through the top and bottom gaps and water layers at the sides of the WTI. This circulation caused a high temperature difference between the wall and the circulating flow. To find a way to prevent this performance deterioration of the WTI we simulated several cases with the smaller gap heights. However, the flow circulation and the higher heat transfer rate were still observed even at a case with the smallest gap, which seems to be hardly achievable in a real installation. Another way of reducing the flow circulation was suggested and also simulated in this study. (authors)

  7. Calcium silicate insulation structure

    DOE Patents [OSTI]

    Kollie, Thomas G. (Oak Ridge, TN); Lauf, Robert J. (Oak Ridge, TN)

    1995-01-01T23:59:59.000Z

    An insulative structure including a powder-filled evacuated casing utilizes a quantity of finely divided synthetic calcium silicate having a relatively high surface area. The resultant structure-provides superior thermal insulating characteristics over a broad temperature range and is particularly well-suited as a panel for a refrigerator or freezer or the insulative barrier for a cooler or a insulated bottle.

  8. Feasibility study for measurement of insulation compaction in the cryogenic rocket fuel storage tanks at Kennedy Space Center by fast/thermal neutron techniques

    SciTech Connect (OSTI)

    Livingston, R. A. [Materials Science and Engineering Dept., U. of Maryland, College Park, MD (United States); Schweitzer, J. S. [Physics Dept., U. of Connecticut, Storrs (United States); Parsons, A. M. [Goddard Space Flight Center, Greenbelt (United States); Arens, E. E. [John F. Kennedy Space Center, FL (United States)

    2014-02-18T23:59:59.000Z

    The liquid hydrogen and oxygen cryogenic storage tanks at John F. Kennedy Space Center (KSC) use expanded perlite as thermal insulation. Some of the perlite may have compacted over time, compromising the thermal performance and also the structural integrity of the tanks. Neutrons can readily penetrate through the 1.75 cm outer steel shell and through the entire 120 cm thick perlite zone. Neutrons interactions with materials produce characteristic gamma rays which are then detected. In compacted perlite the count rates in the individual peaks in the gamma ray spectrum will increase. Portable neutron generators can produce neutron simultaneous fluxes in two energy ranges: fast (14 MeV) and thermal (25 meV). Fast neutrons produce gamma rays by inelastic scattering which is sensitive to Si, Al, Fe and O. Thermal neutrons produce gamma rays by radiative capture in prompt gamma neutron activation (PGNA), which is sensitive to Si, Al, Na, K and H among others. The results of computer simulations using the software MCNP and measurements on a test article suggest that the most promising approach would be to operate the system in time-of-flight mode by pulsing the neutron generator and observing the subsequent die away curve in the PGNA signal.

  9. Theory of Light Emission in Sonoluminescence as Thermal Radiation

    E-Print Network [OSTI]

    Wang-Kong Tse; P. T. Leung

    2006-06-14T23:59:59.000Z

    Based on the model proposed by Hilgenfeldt {\\it at al.} [Nature {\\bf 398}, 401 (1999)], we present here a comprehensive theory of thermal radiation in single-bubble sonoluminescence (SBSL). We first invoke the generalized Kirchhoff's law to obtain the thermal emissivity from the absorption cross-section of a multilayered sphere (MLS). A sonoluminescing bubble, whose internal structure is determined from hydrodynamic simulations, is then modelled as a MLS and in turn the thermal radiation is evaluated. Numerical results obtained from simulations for argon bubbles show that our theory successfully captures the major features observed in SBSL experiments.

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

    E-Print Network [OSTI]

    Schiavon, Stefano; Lee, Kwang Ho

    2013-01-01T23:59:59.000Z

    Predictive Clothing Insulation Models based on Outdoor AirPREDICTIVE CLOTHING INSULATION MODELS ON BUILDING ENERGYthat the clothing insulation is equal to a constant value of

  11. Bremsstrahlung Radiation as Coherent State in Thermal QED

    E-Print Network [OSTI]

    Enke Wang; Jun Xiao; Hanzhong Zhang

    2001-10-23T23:59:59.000Z

    Based on fully finite temperature field theory we investigate the radiation probability in the bremsstrahlung process in thermal QED. It turns out that the infrared divergences resulting from the emission and absorption of the real photons are canceled by the virtual photon exchange processes at finite temperature. The full quantum calculation results for soft photons radiation coincide completely with that obtained in the semi-classical approximation. In the framework of Thermofield Dynamics it is shown that the bremsstrahlung radiation in thermal QED is a coherent state, the quasiclassical behavior of the coherent state leads to above coincidence.

  12. Temperature measurements using multicolor pyrometry in thermal radiation heating environments

    SciTech Connect (OSTI)

    Fu, Tairan, E-mail: trfu@mail.tsinghua.edu.cn [Key Laboratory for Thermal Science and Power Engineering of Ministry of Education, Department of Thermal Engineering, Tsinghua University, Beijing 100084 (China) [Key Laboratory for Thermal Science and Power Engineering of Ministry of Education, Department of Thermal Engineering, Tsinghua University, Beijing 100084 (China); Beijing Key Laboratory of CO2 Utilization and Reduction Technology, Beijing 100084 (China); Liu, Jiangfan; Duan, Minghao; Zong, Anzhou [Key Laboratory for Thermal Science and Power Engineering of Ministry of Education, Department of Thermal Engineering, Tsinghua University, Beijing 100084 (China)] [Key Laboratory for Thermal Science and Power Engineering of Ministry of Education, Department of Thermal Engineering, Tsinghua University, Beijing 100084 (China)

    2014-04-15T23:59:59.000Z

    Temperature measurements are important for thermal-structural experiments in the thermal radiation heating environments such as used for thermal-structural stress analyses. This paper describes the use of multicolor pyrometry for the measurements of diffuse surfaces in thermal radiation environments that eliminates the effects of background radiation reflections and unknown emissivities based on a least-squares algorithm. The near-infrared multicolor pyrometer had a spectral range of 1100–2400 nm, spectrum resolution of 6 nm, maximum sampling frequency of 2 kHz, working distance of 0.6 m to infinity, temperature range of 700–1700 K. The pyrometer wavelength response, nonlinear intensity response, and spectral response were all calibrated. The temperature of a graphite sample irradiated by quartz lamps was then measured during heating and cooling using the least-squares algorithm based on the calibrated irradiation data. The experiments show that higher temperatures and longer wavelengths are more suitable for the thermal measurements in the quartz lamp radiation heating system. This analysis provides a valuable method for temperature measurements of diffuse surfaces in thermal radiation environments.

  13. Numerical analysis of heat transfer by conduction and natural convection in loose-fill fiberglass insulation--effects of convection on thermal performance

    SciTech Connect (OSTI)

    Delmas, A.A.; Wilkes, K.E.

    1992-04-01T23:59:59.000Z

    A two-dimensional code for solving equations of convective heat transfer in porous media is used to analyze heat transfer by conduction and convection in the attic insulation configuration. The particular cases treated correspond to loose-fill fiberglass insulation, which is characterized by high porosity and air permeability. The effects of natural convection on the thermal performance of the insulation are analyzed for various densities, permeabilities, and thicknesses of insulation. With convection increasing the total heat transfer through the insulation, the thermal resistance was found to decrease as the temperature difference across the insulating material increases. The predicted results for the thermal resistance are compared with data obtained in the large-scale climate simulator at the Roof Research Center using the attic test module, where the same phenomenon has already been observed. The way the wood joists within the insulation influence the start of convection is studied for differing thermophysical and dynamic properties of the insulating material. The presence of wood joists induces convection at a lower temperature difference.

  14. Radiation of a neutral polarizable particle moving uniformly through a thermal radiation field

    E-Print Network [OSTI]

    G. V. Dedkov; A. A. Kyasov

    2014-06-25T23:59:59.000Z

    We discuss the properties of thermal electromagnetic radiation produced by a neutral polarizable nanoparticle moving with an arbitrary relativistic velocity in a heated vacuum background with a fixed temperature. We show that the particle in its own rest frame acquires the radiation temperature of vacuum, multiplied by a velocity-dependent factor, and then emits thermal photons predominantly in the forward direction. The intensity of radiation proves to be much higher than for the particle at rest. For metal particles with high energy, the ratio of emitted and absorbed radiation power is proportional to the Lorentz-factor squared.

  15. Load responsive multilayer insulation performance testing

    SciTech Connect (OSTI)

    Dye, S.; Kopelove, A. [Quest Thermal Group, 6452 Fig Street Suite A, Arvada, CO 80004 (United States); Mills, G. L. [Ball Aerospace and Technologies Corp, 1600 Commerce Street, Boulder, CO 80301 (United States)

    2014-01-29T23:59:59.000Z

    Cryogenic insulation designed to operate at various pressures from one atmosphere to vacuum, with high thermal performance and light weight, is needed for cryogenically fueled space launch vehicles and aircraft. Multilayer insulation (MLI) performs well in a high vacuum, but the required vacuum shell for use in the atmosphere is heavy. Spray-on foam insulation (SOFI) is often used in these systems because of its light weight, but can have a higher heat flux than desired. We report on the continued development of Load Responsive Multilayer Insulation (LRMLI), an advanced thermal insulation system that uses dynamic beam discrete spacers that provide high thermal performance both in atmosphere and vacuum. LRMLI consists of layers of thermal radiation barriers separated and supported by micromolded polymer spacers. The spacers have low thermal conductance, and self-support a thin, lightweight vacuum shell that provides internal high vacuum in the insulation. The dynamic load responsive spacers compress to support the external load of a vacuum shell in one atmosphere, and decompress under reduced atmospheric pressure for lower heat leak. Structural load testing was performed on the spacers with various configurations. LRMLI was installed on a 400 liter tank and boil off testing with liquid nitrogen performed at various chamber pressures from one atmosphere to high vacuum. Testing was also performed with an MLI blanket on the outside of the LRMLI.

  16. Thermal Radiation from Nucleons and Mesons

    E-Print Network [OSTI]

    Jan-e Alam; Pradip Roy; Sourav Sarkar

    2003-04-17T23:59:59.000Z

    Thermal photon emission rates due to meson-nucleon interactions have been evaluated. An exhaustive set of reactions involving p(\\bar p), n(\\bar n), rho, omega, a_1, pi and eta is seen to provide a sizeable contribution to the emission rate from hot hadronic matter. Contributions from baryonic resonances are found to be negligibly small.

  17. Cost-Energy Dynamics of Thermal Insulation: Potential Energy Savings and Policy Recommendations

    E-Print Network [OSTI]

    Phung, D. L.; Plaza, H.

    1980-01-01T23:59:59.000Z

    This paper looks at extra insulation for saving energy from the viewpoint of a decision maker. Public and private decisions are distinguished. Profitability and process analyses are combined to obtain a simple trade-off relationship between...

  18. Recent Experiences with Corrosion Beneath Thermal Insulation in a Chemical Plant 

    E-Print Network [OSTI]

    Long, V. C.; Crawley, P. G.

    1984-01-01T23:59:59.000Z

    year old chemical plant located at La Porte, Texas. The program is intended to determine the extent of corrosion damage to major pieces of equipment that has occurred under inhibited calcium silicate insulation finished with aluminum jacketing...

  19. Typical Clothing Ensemble Insulation Levels for Sixteen Body Parts

    E-Print Network [OSTI]

    Lee, Juyoun; Zhang, Hui; Arens, Edward

    2013-01-01T23:59:59.000Z

    Thermal Comfort.1994 CLO Insulation Levels For Sixteen Bodya mesh arm chair whose insulation level was measured. FigureExperimental Conditions. CLO Insulation Levels For Sixteen

  20. Polylogarithmic representation of radiative and thermodynamic properties of thermal radiation in a given spectral range: II. Real-body radiation

    E-Print Network [OSTI]

    Fisenko, Anatoliy I

    2015-01-01T23:59:59.000Z

    The general analytical expressions for the thermal radiative and thermodynamic properties of a real-body are obtained in a finite range of frequencies at different temperatures. The frequency dependence of the spectral emissivity is represented as a power series. The Stefan-Boltzmann law, total energy density, number density of photons, Helmholtz free energy density, internal energy density, enthalpy density, entropy density, heat capacity at constant volume, pressure, and total emissivity are expressed in terms of the polylogarithm functions. The general expressions for the thermal radiative and thermodynamic functions are applied for the study of thermal radiation of liquid and solid zirconium carbide. These functions are calculated using experimental data for the frequency dependence of the normal spectral emissivity in the visible-near infrared range at the melting (freezing) point. The gaps between the thermal radiative and thermodynamic functions of liquid and solid zirconium carbide are observed. The g...

  1. Recent Experiences with Corrosion Beneath Thermal Insulation in a Chemical Plant

    E-Print Network [OSTI]

    Long, V. C.; Crawley, P. G.

    1984-01-01T23:59:59.000Z

    is located on the ship channel east of Ibuston, Texas, a couph:- of miles from Galveston Bay. Prevailing winds are off the Bay, which is salt water, and there is ample rainfall and humidity year round. The Plant is a typical chemical plant. Major.... These dollars are well spent, however, because the plant integrity will be protected and energy savings will accrue from keepinq the insulation dry. I intend to share with you our experiences with corrosion under insulation at the La Porte Plant. The plant...

  2. Experimental Investigation on Thermal Properties of a Steel-jacketed Steam Heating Pipeline with Vacuum Insulation

    E-Print Network [OSTI]

    Na, W.; Zou, P.

    2006-01-01T23:59:59.000Z

    . Vacuum insulation panel [J]. Vacuum. v46,1995: 839?842 [4] R. E. COLLINS, T. M. SIMKO. Current status of the science and technology of vacuum glazing [J]. Solar Energy. V62, 1998(3):189?213 [5] Douglas M. Smith, Alok Maskar, Ulrich Boes. Aerogel...

  3. Emission of non-thermal microwave radiation by a Martian dust storm Christopher Ruf,1

    E-Print Network [OSTI]

    Ruf, Christopher

    and forced by large-scale electric discharge. Thus, the non-thermal radiation was probably caused by electric#12;Emission of non-thermal microwave radiation by a Martian dust storm Christopher Ruf,1 Nilton O report evidence for the emission of non-thermal microwave radiation by a deep Martian dust storm

  4. Jet Quenching via Gravitational Radiation in Thermal AdS

    E-Print Network [OSTI]

    Edward Shuryak; Ho-Ung Yee; Ismail Zahed

    2011-10-04T23:59:59.000Z

    We argue that classical bulk gravitational radiation effects in AdS/CFT, previously ignored because of their subleading nature in the 1/Nc-expansion, are magnified by powers of large Lorentz factors gamma for ultrarelativistic jets, thereby dominating other forms of jet energy loss in holography at finite temperature. We make use of the induced gravitational self-force in thermal AdS5 to estimate its effects. In a thermal medium, relativistic jets may loose most of their energy through longitudinal drag caused by the energy accumulated in their nearby field as they zip through the strongly coupled plasma.

  5. Confined Thermal Multicharged Ions Produced by Synchrotron Radiation 

    E-Print Network [OSTI]

    Church, David A.; Kravis, S. D.; Sellin, I. A.; Levin, J. C.; Short, R. T.; Meron, M.; Johnson, B. M.; Jones, K. W.

    1987-01-01T23:59:59.000Z

    of the accelerated schedule publication is not delayed for receipt of corrections unless requested by the author or noted by the editor Confined thermal multlcharged lons produced by synchrotron radiation D. A. Church and S. D. Kravis Physics Department, Texas... M. Meron, B. M. Johnson, and K. W. Jones Brookhaven National Laboratory, Upton, New York 11973 (Received 2 April 1987) Synchrotron x rays have been used to produce a confined multicharged ion gas near room tem- perature. Comparison of charge-state-number...

  6. Decoherence of matter waves by thermal emission of radiation

    E-Print Network [OSTI]

    Lucia Hackermueller; Klaus Hornberger; Bjoern Brezger; Anton Zeilinger; Markus Arndt

    2004-02-19T23:59:59.000Z

    Emergent quantum technologies have led to increasing interest in decoherence - the processes that limit the appearance of quantum effects and turn them into classical phenomena. One important cause of decoherence is the interaction of a quantum system with its environment, which 'entangles' the two and distributes the quantum coherence over so many degrees of freedom as to render it unobservable. Decoherence theory has been complemented by experiments using matter waves coupled to external photons or molecules, and by investigations using coherent photon states, trapped ions and electron interferometers. Large molecules are particularly suitable for the investigation of the quantum-classical transition because they can store much energy in numerous internal degrees of freedom; the internal energy can be converted into thermal radiation and thus induce decoherence. Here we report matter wave interferometer experiments in which C70 molecules lose their quantum behaviour by thermal emission of radiation. We find good quantitative agreement between our experimental observations and microscopic decoherence theory. Decoherence by emission of thermal radiation is a general mechanism that should be relevant to all macroscopic bodies.

  7. Development of a simplified thermal analysis procedure for insulating glass units 

    E-Print Network [OSTI]

    Klam, Jeremy Wayne

    2009-06-02T23:59:59.000Z

    glass plates for thermal stresses induced by solar irradiance. It is believed that a similar standard can be developed for IG units if a proper understanding of IG thermal stresses can be developed. The objective of this research is to improve...

  8. Electrical wire insulation and electromagnetic coil

    DOE Patents [OSTI]

    Bich, George J. (Penn Hills, PA); Gupta, Tapan K. (Monroeville, PA)

    1984-01-01T23:59:59.000Z

    An electromagnetic coil for high temperature and high radiation application in which glass is used to insulate the electrical wire. A process for applying the insulation to the wire is disclosed which results in improved insulation properties.

  9. Dilution of axion dark radiation by thermal inflation

    E-Print Network [OSTI]

    Hattori, Hironori; Omoto, Naoya; Seto, Osamu

    2015-01-01T23:59:59.000Z

    Axion in the Peccei-Quinn (PQ) mechanism provides a promising solution to the strong CP problem in the standard model of particle physics. Coherently generated PQ scalar fields could dominate the energy density in the early Universe and decay into relativistic axions, which would confront with the current dark radiation constraints. We study the possibility that a thermal inflation driven by a $U(1)$ gauged Higgs field dilutes such axions. A well motivated extra gauged $U(1)$ would be the local $B-L$ symmetry. We also discuss the implication for the case of $U(1)_{B-L}$ and available baryogenesis mechanism in such cosmology.

  10. The physics of non-thermal radiation in microquasars

    E-Print Network [OSTI]

    V. Bosch-Ramon

    2008-10-27T23:59:59.000Z

    Microquasars are binary systems that harbor a normal star and a compact object (black-hole or neutron star), and show relativistic outflows (or jets). The matter that forms these jets is of likely stellar origin, previously expelled from the star and trapped in the potential well of the compact object. This matter is accreted by the compact object, forming a disk due to its angular momentum, and is eventually ejected in the form of a bipolar outflow (the jets), which generates radio emission and could also be a very high-energy emitter. To study and understand the radiation from microquasars, there is a set of elements that can play a major role and are to be taken into account: the photons and the expelled matter from the star in the case of high-mass systems; the accreted matter radiation; the jet; the magnetic field carried by the jet or filling the binary system; and the medium surrounding the microquasar at large scales (~pc). In this lecture, we consider these elements of the microquasar scenario and briefly describe the physical conditions and processes involved in the production of non-thermal radiation from radio to gamma-rays. The required energetics, particle acceleration and transport, several radiative mechanisms, and the impact of different photon absorption processes, are discussed.

  11. Versatile Indian sari: Clothing insulation with different drapes of typical sari ensembles

    E-Print Network [OSTI]

    Indraganti, Madhavi; Lee, Juyoun; Zhang, Hui; Arens, Edward

    2014-01-01T23:59:59.000Z

    Extension of the Clothing Insulation Database for Standardand air movement on that insulation. , s.l. : s.n. Havenith,Estimation of the thermal insulation and evaporative

  12. Parylene-based active micro space radiator with thermal contact switch

    SciTech Connect (OSTI)

    Ueno, Ai; Suzuki, Yuji [Department of Mechanical Engineering, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan)

    2014-03-03T23:59:59.000Z

    Thermal management is crucial for highly functional spacecrafts exposed to large fluctuations of internal heat dissipation and/or thermal boundary conditions. Since thermal radiation is the only means for heat removal, effective control of radiation is required for advanced space missions. In the present study, a MEMS (Micro Electro Mechanical Systems) active radiator using the contact resistance change has been proposed. Unlike previous bulky thermal louvers/shutters, higher fill factor can be accomplished with an array of electrostatically driven micro diaphragms suspended with polymer tethers. With an early prototype developed with parylene MEMS technologies, radiation heat flux enhancement up to 42% has been achieved.

  13. Design of a variable-conductance vacuum insulation

    SciTech Connect (OSTI)

    Benson, D K; Potter, T F; Tracy, C E

    1994-01-01T23:59:59.000Z

    This paper describes one approach to the design of a variable-conductance vacuum insulation. In this design, the vacuum insulation consists of a permanently sealed, thin sheet steel, evacuated envelope of whatever geometry is required for the application. The steel envelope is supported internally against the atmospheric pressure loads by an array of discrete, low-conductance, ceramic supports, and radiative heat transfer is blocked by layers of thin metal radiation shields. Thermal conductance through this insulation is controlled electronically by changing the temperature of a small metal hydride connected to the vacuum envelope. The hydride reversibly absorbs/desorbs hydrogen to produce a hydrogen pressure typically within the range from less than 10{sup {minus}6} to as much as 1 torr. Design calculations are compared with results from laboratory tests of bench scale samples, and some possible automotive applications for this variable-conductance vacuum insulation are suggested.

  14. Thermal Instability of Protected End States in a 1-D Topological Insulator

    E-Print Network [OSTI]

    O. Viyuela; A. Rivas; M. A. Martin-Delgado

    2012-10-23T23:59:59.000Z

    We have studied the dynamical thermal effects on the protected end states of a topological insula- tor (TI) when it is considered as an open quantum system in interaction with a noisy environment at a certain temperature T . As a result, we find that protected end states in a TI become unstable and decay with time. Very remarkably, the interaction with the thermal environment (fermion-boson) respects chiral symmetry, which is the symmetry responsible for the protection (robustness) of the end states in this TI when it is isolated from the environment. Therefore, this mechanism makes end states unstable while preserving their protecting symmetry. Our results have immediate practical implications in recently proposed simulations of TI using cold atoms in optical lattices. Accordingly, we have computed lifetimes of topological end states for these physical implementations that are useful to make those experiments realistic.

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

    SciTech Connect (OSTI)

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

    2002-02-26T23:59:59.000Z

    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.

  16. Laboratory test results on the thermal resistance of polyisocyanurate foamboard insulation blown with CFC-11 substitutes: A cooperative industry/government project

    SciTech Connect (OSTI)

    McElroy, D.L.; Graves, R.S.; Yarbrough, D.W.; Weaver, F.J.

    1991-09-01T23:59:59.000Z

    The fully halogenated chlorofluorocarbon gases (CFC-11 and CFC-12) are used as blowing agents for foam insulations for building and appliance applications. The thermal resistance per unit thickness of these insulations is greater than that of other commercially available insulations. Mandated reductions in the production of these chemicals may lead to less efficient substitutes and increase US energy consumption by one quad or more. This report describes laboratory thermal and aging tests on a set of industry-produced, experimental polyisocyanurate (PIR) laminate boardstock to evaluate the viability of hydrochlorofluorocarbons (HCFSs) as alternative blowing agents to chlorofluorcarbon-11 (CFC-11). The PIR boards were blown with five gases: CFC-11, HCFC- 123, HCFC-141b, and 50/50 and 65/35 blends of HCFC-123/HCFC-141b. These HCFC gases have a lower ozone depletion potential than CFC-11 or CFC-12. Apparent thermal conductivity (k) was determined from 0 to 50{degrees}C. Results on the laminate boards provide an independent laboratory check on the increase in k observed for field exposure in the Roof Thermal Research Apparatus (RTRA). The measured laboratory increase in k was between 8 and 11% after a 240-d field exposure in the RTRA. Results are reported on a thin-specimen, aging procedure to establish the long-term thermal resistance of gas-filled foams. These thin specimens were planed from the industry-produced boardstock foams and aged at 75 and 150{degrees}F for up to 300 d. The resulting k-values were correlated with an exponential dependency on (diffusion coefficient {times} time){sup {1/2}}/thickness and provided diffusion coefficients for air components into, and blowing agent out of, the foam. This aging procedure was used to predict the five-year thermal resistivity of the foams. The thin-specimen aging procedure is supported with calculations by a computer model for aging of foams. 43 refs., 33 figs., 25 tabs.

  17. STATE OF CALIFORNIA INSULATION STAGE CHECKLIST

    E-Print Network [OSTI]

    STATE OF CALIFORNIA INSULATION STAGE CHECKLIST CEC-CF-6R-ENV-22 (Revised 05/12) CALIFORNIA ENERGY COMMISSION INSTALLATION CERTIFICATE CF-6R-ENV-22 Quality Insulation Installation (QII) - Insulation Stage be insulated in a manner that resists thermal bridging of the assembly separating conditioned from

  18. The application of expansion foam on liquefied natural gas (LNG) to suppress LNG vapor and LNG pool fire thermal radiation

    E-Print Network [OSTI]

    Suardin, Jaffee Arizon

    2009-05-15T23:59:59.000Z

    Liquefied Natural Gas (LNG) hazards include LNG flammable vapor dispersion and LNG pool fire thermal radiation. A large LNG pool fire emits high thermal radiation thus preventing fire fighters from approaching and extinguishing the fire. One...

  19. Measuring the Impact of Experimental Parameters upon the Estimated Thermal Conductivity of Closed-Cell Foam Insulation Subjected to an Accelerated Aging Protocol

    SciTech Connect (OSTI)

    Stovall, Therese K [ORNL] [ORNL; Bogdan, mary [Honeywell, Inc.] [Honeywell, Inc.

    2008-01-01T23:59:59.000Z

    The thermal conductivity of many closed-cell foam insulation products changes over time as production gases diffuse out of the cell matrix and atmospheric gases diffuse into the cells. Thin slicing has been shown to be an effective means of accelerating this process in such a way as to produce meaningful results. Recent efforts to produce a more prescriptive version of the ASTM standard test method have led to the initiation of a broad ruggedness test. This test includes the aging of full size insulation specimens for time periods up to five years for later comparison to the predicted results. Experimental parameters under investigation include: slice thickness, slice origin (at the surface or from the core of the slab), thin slice stack composition, product facings, original product thickness, product density, and product type. This paper will cover the structure of the ruggedness test and provide a glimpse of some early trends

  20. Radiative Thermal Noise for Transmissive Optics in Gravitational-Wave Detectors

    E-Print Network [OSTI]

    Sheila Dwyer; Stefan W. Ballmer

    2014-08-07T23:59:59.000Z

    Radiative losses have traditionally been neglected in the calculation of thermal noise of transmissive optical elements because for the most commonly used geometries they are small compared to losses due to thermal conduction. We explore the use of such transmissive optical elements in extremely noise-sensitive environments such as the arm cavities of future gravitational-wave interferometers. This drives us to a geometry regime where radiative losses are no longer negligible. In this paper we derive the thermo-refractive noise associated with such radiative losses and compare it to other known sources of thermal noise.

  1. STATE OF CALIFORNIA ENVELOPE INSULATION; ROOFING; FENESTRATION

    E-Print Network [OSTI]

    STATE OF CALIFORNIA ENVELOPE ­ INSULATION; ROOFING; FENESTRATION CEC-CF-6R-ENV-01 (Revised 08/09) CALIFORNIA ENERGY COMMISSION INSTALLATION CERTIFICATE CF-6R-ENV-01 Envelope ­ Insulation; Roofing:__________________________________ Brand Name:_______________________________ Thickness (inches):_________________________ Thermal

  2. Flashlamp radiation recycling for enhanced pumping efficiency and reduced thermal load

    DOE Patents [OSTI]

    Jancaitis, Kenneth S. (Pleasant Hill, CA); Powell, Howard T. (Livermore, CA)

    1989-01-01T23:59:59.000Z

    A method for recycling laser flashlamp radiation in selected wavelength ranges to decrease thermal loading of the solid state laser matrix while substantially maintaining the pumping efficiency of the flashlamp.

  3. Near-field thermal radiation transfer controlled by plasmons in graphene

    E-Print Network [OSTI]

    Ilic, Ognjen

    It is shown that thermally excited plasmon-polariton modes can strongly mediate, enhance, and tune the near-field radiation transfer between two closely separated graphene sheets. The dependence of near-field heat exchange ...

  4. Method and device for predicting wavelength dependent radiation influences in thermal systems

    DOE Patents [OSTI]

    Kee, Robert J. (864 Lucille St., Livermore, CA 94550); Ting, Aili (7329 Stonedale Dr., Pleasanton, CA 94558)

    1996-01-01T23:59:59.000Z

    A method and apparatus for predicting the spectral (wavelength-dependent) radiation transport in thermal systems including interaction by the radiation with partially transmitting medium. The predicted model of the thermal system is used to design and control the thermal system. The predictions are well suited to be implemented in design and control of rapid thermal processing (RTP) reactors. The method involves generating a spectral thermal radiation transport model of an RTP reactor. The method also involves specifying a desired wafer time dependent temperature profile. The method further involves calculating an inverse of the generated model using the desired wafer time dependent temperature to determine heating element parameters required to produce the desired profile. The method also involves controlling the heating elements of the RTP reactor in accordance with the heating element parameters to heat the wafer in accordance with the desired profile.

  5. Thermal heat radiation, near-field energy density and near-field radiative heat transfer of coated materials

    E-Print Network [OSTI]

    Svend-Age Biehs

    2011-03-15T23:59:59.000Z

    We investigate the thermal radiation and thermal near-field energy density of a metal-coated semi-infinite body for different substrates. We show that the surface polariton coupling within the metal coating leads to an enhancement of the TM-mode part of the thermal near-field energy density when a polar substrate is used. In this case the result obtained for a free standing metal film is retrieved. In contrast, in the case of a metal substrate there is no enhancement in the TM-mode part, as can also be explained within the framework of surface plasmon coupling within the coating. Finally, we discuss the influence of the enhanced thermal energy density on the near-field radiative heat transfer between a simple semi-infinite and a coated semi-infinite body for different material combinations.

  6. MODELLING RADIATIVELY ACTIVE WATER-ICE CLOUDS: IMPACT ON THE THERMAL STRUCTURE AND WATER CYCLE.

    E-Print Network [OSTI]

    Madeleine, Jean-Baptiste

    MODELLING RADIATIVELY ACTIVE WATER-ICE CLOUDS: IMPACT ON THE THERMAL STRUCTURE AND WATER CYCLE. J. The essential role of water-ice clouds in shaping the thermal structure of the martian atmosphere has been long presumed [1] but neglected in GCMs because of the lack of observations and difficulty to predict

  7. Thermal radiation of laser heated niobium clusters Nb{sub N}{sup +}, 8 ? N ? 22

    SciTech Connect (OSTI)

    Hansen, Klavs [Department of Physics, University of Gothenburg, 41296 Gothenburg (Sweden); Li, Yejun; Kaydashev, Vladimir; Janssens, Ewald [Laboratory of Solid State Physics and Magnetism, KU Leuven, B-3001 Leuven (Belgium)

    2014-07-14T23:59:59.000Z

    The thermal radiation from small, laser heated, positively charged niobium clusters has been measured. The emitted power was determined by the quenching effect on the metastable decay, employing two different experimental protocols. The radiative power decreases slightly with cluster size and shows no strong size-to-size variations. The magnitude is 40–50 keV/s at the timescale of several microseconds, which is the measured crossover time from evaporative to radiative cooling.

  8. Radio-transparent multi-layer insulation for radiowave receivers

    SciTech Connect (OSTI)

    Choi, J. [Korea University, Anam-dong Seongbuk-gu, Seoul 136-713 (Korea, Republic of)] [Korea University, Anam-dong Seongbuk-gu, Seoul 136-713 (Korea, Republic of); Ishitsuka, H. [Department of Particle and Nuclear Physics, School of High Energy Accelerator Science, The Graduate University for Advanced Studies (SOKENDAI), Shonan Village, Hayama, Kanagawa 240-0193 (Japan)] [Department of Particle and Nuclear Physics, School of High Energy Accelerator Science, The Graduate University for Advanced Studies (SOKENDAI), Shonan Village, Hayama, Kanagawa 240-0193 (Japan); Mima, S. [Terahertz Sensing and Imaging Team, Terahertz-wave Research Group, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan)] [Terahertz Sensing and Imaging Team, Terahertz-wave Research Group, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Oguri, S., E-mail: shugo@post.kek.jp [Institute of Particle and Nuclear Studies, High Energy Accelerator Research Organization (KEK), Oho, Tsukuba, Ibaraki 305-0801 (Japan); Takahashi, K. [Terahertz Sensing and Imaging Team, Terahertz-wave Research Group, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan) [Terahertz Sensing and Imaging Team, Terahertz-wave Research Group, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Department of Physics, Tohoku University, Sendai, Miyagi 980-8578 (Japan); Tajima, O. [Department of Particle and Nuclear Physics, School of High Energy Accelerator Science, The Graduate University for Advanced Studies (SOKENDAI), Shonan Village, Hayama, Kanagawa 240-0193 (Japan) [Department of Particle and Nuclear Physics, School of High Energy Accelerator Science, The Graduate University for Advanced Studies (SOKENDAI), Shonan Village, Hayama, Kanagawa 240-0193 (Japan); Institute of Particle and Nuclear Studies, High Energy Accelerator Research Organization (KEK), Oho, Tsukuba, Ibaraki 305-0801 (Japan)

    2013-11-15T23:59:59.000Z

    In the field of radiowave detection, enlarging the receiver aperture to enhance the amount of light detected is essential for greater scientific achievements. One challenge in using radio transmittable apertures is keeping the detectors cool. This is because transparency to thermal radiation above the radio frequency range increases the thermal load. In shielding from thermal radiation, a general strategy is to install thermal filters in the light path between aperture and detectors. However, there is difficulty in fabricating metal mesh filters of large diameters. It is also difficult to maintain large diameter absorptive-type filters in cold because of their limited thermal conductance. A technology that maintains cold conditions while allowing larger apertures has been long-awaited. We propose radio-transparent multi-layer insulation (RT-MLI) composed from a set of stacked insulating layers. The insulator is transparent to radio frequencies, but not transparent to infrared radiation. The basic idea for cooling is similar to conventional multi-layer insulation. It leads to a reduction in thermal radiation while maintaining a uniform surface temperature. The advantage of this technique over other filter types is that no thermal links are required. As insulator material, we used foamed polystyrene; its low index of refraction makes an anti-reflection coating unnecessary. We measured the basic performance of RT-MLI to confirm that thermal loads are lowered with more layers. We also confirmed that our RT-MLI has high transmittance to radiowaves, but blocks infrared radiation. For example, RT-MLI with 12 layers has a transmittance greater than 95% (lower than 1%) below 200 GHz (above 4 THz). We demonstrated its effects in a system with absorptive-type filters, where aperture diameters were 200 mm. Low temperatures were successfully maintained for the filters. We conclude that this technology significantly enhances the cooling of radiowave receivers, and is particularly suitable for large-aperture systems. This technology is expected to be applicable to various fields, including radio astronomy, geo-environmental assessment, and radar systems.

  9. Neutron star envelopes and thermal radiation from the magnetic surface

    E-Print Network [OSTI]

    J. Ventura; A. Y. Potekhin

    2001-03-31T23:59:59.000Z

    The thermal structure of neutron star envelopes is discussed with emphasis on analytic results. Recent progress on the effect of chemical constitution and high magnetic fields on the opacities and the thermal structure is further reviewed in view of the application to pulsar cooling and magnetars.

  10. Bridging conduction and radiation : investigating thermal transport in nanoscale gaps

    E-Print Network [OSTI]

    Chiloyan, Vazrik

    2015-01-01T23:59:59.000Z

    Near field radiation transfer between objects separated by small gaps is a widely studied field in heat transfer and has become more important than ever. Many technologies such as heat assisted magnetic recording, aerogels, ...

  11. Radiation and Thermal Ageing of Nuclear Waste Glass

    SciTech Connect (OSTI)

    Weber, William J [ORNL

    2014-01-01T23:59:59.000Z

    The radioactive decay of fission products and actinides incorporated into nuclear waste glass leads to self-heating and self-radiation effects that may affect the stability, structure and performance of the glass in a closed system. Short-lived fission products cause significant self-heating for the first 600 years. Alpha decay of the actinides leads to self-radiation damage that can be significant after a few hundred years, and over the long time periods of geologic disposal, the accumulation of helium and radiation damage from alpha decay may lead to swelling, microstructural evolution and changes in mechanical properties. Four decades of research on the behavior of nuclear waste glass are reviewed.

  12. Characterization of Min-K TE-1400 Thermal Insulation (Two-Year Gradient Stress Relaxation Testing Update)

    SciTech Connect (OSTI)

    Hemrick, James Gordon [ORNL; Lara-Curzio, Edgar [ORNL; King, James [ORNL

    2009-09-01T23:59:59.000Z

    Min-K 1400TE insulation material was characterized at Oak Ridge National Laboratory for use in structural applications under gradient temperature conditions. A previous report (ORNL/TM-2008/089) discusses the testing and results from the original three year duration of the project. This testing included compression testing to determine the effect of sample size and test specimen geometry on the compressive strength of Min-K, subsequent compression testing on cylindrical specimens to determine loading rates for stress relaxation testing, isothermal stress relaxation testing, and gradient stress relaxation testing. This report presents the results from the continuation of the gradient temperature stress relaxation testing and the resulting updated modeling.

  13. Confined Thermal Multicharged Ions Produced by Synchrotron Radiation

    E-Print Network [OSTI]

    Church, David A.; Kravis, S. D.; Sellin, I. A.; Levin, J. C.; Short, R. T.; Meron, M.; Johnson, B. M.; Jones, K. W.

    1987-01-01T23:59:59.000Z

    energy transfer. We have used the "white" radiation on the X- 26C beam line of the National Synchrotron Light Source (NSLS) at Brookhaven National Laboratory to generate multicharged argon ions in a Penning ion trap, using pro- posed methods designed... M. Meron, B. M. Johnson, and K. W. Jones Brookhaven National Laboratory, Upton, New York 11973 (Received 2 April 1987) Synchrotron x rays have been used to produce a confined multicharged ion gas near room tem- perature. Comparison of charge...

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

    E-Print Network [OSTI]

    Schiavon, Stefano; Lee, Kwang Ho

    2013-01-01T23:59:59.000Z

    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

  15. Einstein's coefficients and the wave-particle duality in the theory of thermal radiation

    E-Print Network [OSTI]

    Fedor V. Prigara

    2005-01-19T23:59:59.000Z

    It is shown that the concept of elementary resonator in the theory of thermal radiation implies the indivisible connection between particles (photons) and electromagnetic waves. This wave-particle duality covers both the Wien and Rayleigh-Jeans regions of spectrum.

  16. The energy distribution of atoms in the field of thermal blackbody radiation

    E-Print Network [OSTI]

    F. V. Prigara

    2002-02-06T23:59:59.000Z

    Using the principle of detailed balance and the assumption on the absorption cross-section consistent with available astrophysical data, we obtain the energy distribution of atoms in the field of thermal blackbody radiation and show that this distribution diverges from the Boltzmann law.

  17. The 1D Iterative Model for Predicting Thermal Radiation from a Jet Fire

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    manuscript, published in "6. International Seminar on Fire and Explosion Hazards (FEH), Leeds : UnitedThe 1D Iterative Model for Predicting Thermal Radiation from a Jet Fire Leroy, G.* and Duplantier of the current jet fire models used in the accidental fire risks department are semi- empirical. They depend

  18. Radiation and Thermal Analysis of Superconducting Quadrupoles in the Interaction Region of Linear Collider

    SciTech Connect (OSTI)

    Drozhdin, A.I.; Kashikhin, V.V.; Kashikhin, V.S.; Lopes, M.L.; Mokhov, N.V.; Zlobin, A.V.; /Fermilab; Seryi, Andrei; /SLAC

    2011-10-14T23:59:59.000Z

    Radiation heat deposition in the superconducting magnets of the Interaction Region (IR) of a linear collider can be a serious issue that limits the magnet operating margins and shortens the material lifetime. Radiation and thermal analyses of the IR quadrupoles in the incoming and extraction beam lines of the ILC are performed in order to determine the magnet limits. This paper presents an analysis of the radial, azimuthal and longitudinal distributions of heat deposition in the incoming and disrupted beam doublets. Operation margins of the magnets based on NbTi superconductor are calculated and compared. The radiation and thermal analysis of the ILC IR quadrupoles based on Rutherford type cables was performed. It was found that the peak radiation heat deposition takes place in the second extraction quadrupole QFEX2. The maximum power density in the coil is {approx}17mW/g. This is rather high, comparing to the proton machines (LHC). However, the fast radial decay of the heat deposition together with the high thermal conductivity of the Rutherford type cable limits the coil temperatures to a moderate level. It was determined that both 2-layer and 4-layer QFEX2 magnet designs have thermal margins of a factor of {approx}4 at the nominal gradient of 31.3 T/m. Because of the large margins, these magnets can easily accommodate possible changes in the IR optics and heat deposition levels.

  19. Calculation of thermal fluxes of plasma torch reradiation under the action of laser radiation on a condensed target

    SciTech Connect (OSTI)

    Rudenko, V. V. [Russian Federation Ministry of Defense, 12th Central Scientific Research Institute (Russian Federation)

    2010-12-15T23:59:59.000Z

    The problem of laser deposition with allowance for thermal radiation transport inside and outside the laser torch is considered in a multigroup approximation. The energy fluxes of laser torch thermal radiation onto a target in the far and near zones are calculated as functions of time and the character of the exposure. It is shown that absorption of thermal fluxes in the substrate and target in the course of laser deposition results in their substantial heating. The possibility of diagnosing thermal radiation fluxes from the laser torch by using photodetectors is demonstrated.

  20. Finite element analysis of the distortion of a crystal monochromator from synchrotron radiation thermal loading

    SciTech Connect (OSTI)

    Edwards, W.R.; Hoyer, E.H.; Thompson, A.C.

    1985-10-01T23:59:59.000Z

    The first crystal of the Brown-Hower x-ray monochromator of the LBL-EXXON 54 pole wiggler beamline at Stanford Synchrotron Radiation Laboratory (SSRL) is subjected to intense synchrotron radiation. To provide an accurate thermal/structural analysis of the existing monochromator design, a finite element analysis (FEA) was performed. A very high and extremely localized heat flux is incident on the Si (220) crystal. The crystal, which possesses pronouncedly temperature-dependent orthotropic properties, in combination with the localized heat load, make the analysis ideally suited for finite element techniques. Characterization of the incident synchrotron radiation is discussed, followed by a review of the techniques employed in modeling the monochromator and its thermal/structural boundary conditions. The results of the finite element analysis, three-dimensional temperature distributions, surface displacements and slopes, and stresses, in the area of interest, are presented. Lastly, the effects these results have on monochromator output flux and resolution are examined.

  1. Non-thermal radiation from a runaway massive star

    E-Print Network [OSTI]

    Romero, Gustavo E; Peri, Cintia S; Marti, Josep; Araudo, Anabella T

    2010-01-01T23:59:59.000Z

    We present a study of the radio emission from a massive runaway star. The star forms a bow shock that is clearly observed in the infrared. We have performed VLA observations under the assumption that the reverse shock in the stellar wind might accelerate charged particles up to relativistic energies. Non-thermal radio emission of synchrotron origin has been detected, confirming the hypothesis. We have then modeled the system and we predict a spectral energy distribution that extends up to gamma-rays. Under some simplifying assumptions, we find that the intensity at high energies is too low to be detected by current instruments, but the future Cherenkov Telescope Array might detect the source.

  2. High-efficiency scintillation detector for combined detection of thermal and fast neutrons and gamma radiation

    DOE Patents [OSTI]

    Chiles, M.M.; Mihalczo, J.T.; Blakeman, E.D.

    1987-02-27T23:59:59.000Z

    A scintillation based radiation detector for the combined detection of thermal neutrons, high-energy neutrons and gamma rays in a single detecting unit. The detector consists of a pair of scintillators sandwiched together and optically coupled to the light sensitive face of a photomultiplier tube. A light tight radiation pervious housing is disposed about the scintillators and a portion of the photomultiplier tube to hold the arrangement in assembly and provides a radiation window adjacent the outer scintillator through which the radiation to be detected enters the detector. The outer scintillator is formed of a material in which scintillations are produced by thermal-neutrons and the inner scintillator is formed of a material in which scintillations are produced by high-energy neutrons and gamma rays. The light pulses produced by events detected in both scintillators are coupled to the photomultiplier tube which produces a current pulse in response to each detected event. These current pulses may be processed in a conventional manner to produce a count rate output indicative of the total detected radiation event count rate. Pulse discrimination techniques may be used to distinguish the different radiations and their energy distribution.

  3. Interaction with thermal radiation in the free expansion and mixing of ideal gases and Gibbs' paradox in classical thermodynamics

    E-Print Network [OSTI]

    A. Paglietti

    2009-04-26T23:59:59.000Z

    The standard theory of ideal gases ignores the interaction of the gas particles with the thermal radiation (photon gas) that fills the otherwise vacuum space between them. This is an unphysical feature of the theory since every material in this universe, and hence also the particles of a gas, absorbs and radiates thermal energy. The interaction with the thermal radiation that is contained within the volume of the body may be important in gases since the latter, unlike solids and liquids, are capable of undergoing conspicuous volume changes. Taking this interaction into account makes the behaviour of the ideal gases more realistic and removes Gibbs' paradox.

  4. Joint Industry/Government Research Project: Comparison of thermal aging for roof exposures and thin-specimens of experimental polyisocyanurate insulation foamed with alternative blowing agents

    SciTech Connect (OSTI)

    Graves, R.S.; Christian, J.E.; McElroy, D.L.

    1991-01-01T23:59:59.000Z

    This paper reports apparent thermal conductivity (k) values from field exposures and laboratory aging of a set of industry-produced, experimental polyisocyanurate (PIR) laminated boardstock foamed with hydrochlorofluorocarbons (HCFCs) as alternative to chlorofluorocarbons (CFCs). The k-values were determined from 0 to 50{degree}C using techniques that meet ASTM C 1114 (Thin Heater Apparatus) and ASTM C 518 (Heat Flow Meter Apparatus). The increase in k observed for field exposure in the ORNL Roof Thermal Research Apparatus (RTRA) was confirmed by independent laboratory tests. The observed laboratory increase in k was about the same, between 17 and 22%, for all three blowing agent foams for a 450 day field exposure in the RTRA. Thin specimens were planed from the industry-produced boardstock foams and aged at 24 and 65{degree}C for up to 460 days. The foams blown with alternative blowing agents exhibited long-term k-values 7 to 15% above those for CFC foams under similar conditions. Field exposures were conducted on specimens under single ply EPDM membranes in the RTRA for over 680 days. Hourly averages of panel temperature and heat flux were analyzed to obtain k as a function of mean insulation temperature on a week-by-week basis. The k-values derived from the field data provided effective diffusion coefficients for air in the foam, which were within 7% of those obtained from the thin-specimen aging procedure at 24%C except for one sample. The relative performance of test specimens of HCFC-141b under a black and under a white membrane is reported, and data suggest that differences are relatively small. 26 refs., 10 figs., 8 tabs.

  5. Gas filled panel insulation

    DOE Patents [OSTI]

    Griffith, B.T.; Arasteh, D.K.; Selkowitz, S.E.

    1993-12-14T23:59:59.000Z

    A structural or flexible highly insulative panel which may be translucent, is formed from multi-layer polymeric material in the form of an envelope surrounding a baffle. The baffle is designed so as to minimize heat transfer across the panel, by using material which forms substantially closed spaces to suppress convection of the low conductivity gas fill. At least a portion of the baffle carries a low emissivity surface for suppression of infrared radiation. 18 figures.

  6. Superconducting Topological Insulators

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

    Superconducting Topological Insulators Superconducting Topological Insulators Print Wednesday, 26 January 2011 00:00 Three-dimensional topological insulators (TIs), discovered...

  7. Heat blanketing envelopes and thermal radiation of strongly magnetized neutron stars

    E-Print Network [OSTI]

    A. Y. Potekhin; G. Chabrier; D. G. Yakovlev

    2007-09-04T23:59:59.000Z

    Strong (B >> 10^9 G) and superstrong (B > 10^{14} G) magnetic fields profoundly affect many thermodynamic and kinetic characteristics of dense plasmas in neutron star envelopes. In particular, they produce strongly anisotropic thermal conductivity in the neutron star crust and modify the equation of state and radiative opacities in the atmosphere, which are major ingredients of the cooling theory and spectral atmosphere models. As a result, both the radiation spectrum and the thermal luminosity of a neutron star can be affected by the magnetic field. We briefly review these effects and demonstrate the influence of magnetic field strength on the thermal structure of an isolated neutron star, putting emphasis on the differences brought about by the superstrong fields and high temperatures of magnetars. For the latter objects, it is important to take proper account of a combined effect of the magnetic field on thermal conduction and neutrino emission at densities \\rho > 10^{10} g cm^{-3}. We show that the neutrino emission puts a B-dependent upper limit on the effective surface temperature of a cooling neutron star.

  8. Nonlinear vs. bolometric radiation response and phonon thermal conductance in graphene-superconductor junctions

    SciTech Connect (OSTI)

    Vora, Heli; Nielsen, Bent; Du, Xu [Department of Physics and Astronomy, Stony Brook University, Stony Brook, New York (United States)

    2014-02-21T23:59:59.000Z

    Graphene is a promising candidate for building fast and ultra-sensitive bolometric detectors due to its weak electron-phonon coupling and low heat capacity. In order to realize a practical graphene-based bolometer, several important issues, including the nature of radiation response, coupling efficiency to the radiation and the thermal conductance need to be carefully studied. Addressing these issues, we present graphene-superconductor junctions as a viable option to achieve efficient and sensitive bolometers, with the superconductor contacts serving as hot electron barriers. For a graphene-superconductor device with highly transparent interfaces, the resistance readout in the presence of radio frequency radiation is dominated by non-linear response. On the other hand, a graphene-superconductor tunnel device shows dominantly bolometric response to radiation. For graphene devices fabricated on SiO{sub 2} substrates, we confirm recent theoretical predictions of T{sup 2} temperature dependence of phonon thermal conductance in the presence of disorder in the graphene channel at low temperatures.

  9. The role of radiation transport in the thermal response of semitransparent materials to localized laser heating

    SciTech Connect (OSTI)

    Colvin, Jeffrey; Shestakov, Aleksei; Stoelken, James; Vignes, Ryan [Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, CA 94551 (United States)

    2011-03-01T23:59:59.000Z

    Lasers are widely used to modify the internal structure of semitransparent materials for a wide variety of applications, including waveguide fabrication and laser glass damage healing. The gray diffusion approximation used in past models to describe radiation cooling is not adequate for these materials, particularly near the heated surface layer. In this paper we describe a computational model based upon solving the radiation transport equation in 1D by the P{sub n} method with {approx}500 photon energy bands, and by multi-group radiation diffusion in 2D with fourteen photon energy bands. The model accounts for the temperature-dependent absorption of infrared laser light and subsequent redistribution of the deposited heat by both radiation and conductive transport. We present representative results for fused silica irradiated with 2-12 W of 4.6 or 10.6 {mu}m laser light for 5-10 s pulse durations in a 1 mm spot, which is small compared to the diameter and thickness of the silica slab. We show that, unlike the case for bulk heating, in localized infrared laser heating radiation transport plays only a very small role in the thermal response of silica.

  10. Quantum corrected non-thermal radiation spectrum from the tunnelling mechanism

    E-Print Network [OSTI]

    Subenoy Chakraborty; Subhajit Saha; Christian Corda

    2015-05-28T23:59:59.000Z

    Tunnelling mechanism is today considered a popular and widely used method in describing Hawking radiation. However, in relation to black hole (BH) emission, this mechanism is mostly used to obtain the Hawking temperature by comparing the probability of emission of an outgoing particle with the Boltzmann factor. On the other hand, Banerjee and Majhi reformulated the tunnelling framework deriving a black body spectrum through the density matrix for the outgoing modes for both the Bose-Einstein distribution and the Fermi-Dirac distribution. In contrast, Parikh and Wilczek introduced a correction term performing an exact calculation of the action for a tunnelling spherically symmetric particle and, as a result, the probability of emission of an outgoing particle corresponds to a non-strictly thermal radiation spectrum. Recently, one of us (C. Corda) introduced a BH effective state and was able to obtain a non-strictly black body spectrum from the tunnelling mechanism corresponding to the probability of emission of an outgoing particle found by Parikh and Wilczek. The present work introduces the quantum corrected effective temperature and the corresponding quantum corrected effective metric is written using Hawking's periodicity arguments. Thus, we obtain further corrections to the non-strictly thermal BH radiation spectrum as the final distributions take into account both the BH dynamical geometry during the emission of the particle and the quantum corrections to the semiclassical Hawking temperature.

  11. Fiber-optic thermometer application of thermal radiation from rare-earth end-doped SiO{sub 2} fiber

    SciTech Connect (OSTI)

    Katsumata, Toru, E-mail: katsumat@toyo.jp; Morita, Kentaro; Komuro, Shuji; Aizawa, Hiroaki [Faculty of Science and Engineering, Toyo University, 2100 Kujirai, Kawagoe, Saitama 350-8585 (Japan)

    2014-08-15T23:59:59.000Z

    Visible light thermal radiation from SiO{sub 2} glass doped with Y, La, Ce, Pr, Nd, Eu, Tb, Dy, Ho, Er, Tm, Yb, and Lu were studied for the fiber-optic thermometer application based on the temperature dependence of thermal radiation. Thermal radiations according to Planck's law of radiation are observed from the SiO{sub 2} fibers doped with Y, La, Ce, Pr, Eu, Tb, and Lu at the temperature above 1100 K. Thermal radiations due to f-f transitions of rare-earth ions are observed from the SiO{sub 2} fibers doped with Nd, Dy, Ho, Er, Tm, and Yb at the temperature above 900 K. Peak intensities of thermal radiations from rare-earth doped SiO{sub 2} fibers increase sensitively with temperature. Thermal activation energies of thermal radiations by f-f transitions seen in Nd, Dy, Ho, Er, Tm, and Yb doped SiO{sub 2} fibers are smaller than those from SiO{sub 2} fibers doped with Y, La, Ce, Pr, Eu, Tb, and Lu. Thermal radiation due to highly efficient f-f transitions in Nd, Dy, Ho, Er, Tm, and Yb ions emits more easily than usual thermal radiation process. Thermal radiations from rare-earth doped SiO{sub 2} are potentially applicable for the fiber-optic thermometry above 900 K.

  12. Millimeter radiation from a 3D model of the solar atmosphere I. Diagnosing chromospheric thermal structure

    E-Print Network [OSTI]

    Loukitcheva, Maria; Carlsson, Mats; White, Stephen

    2015-01-01T23:59:59.000Z

    Aims. We use advanced 3D NLTE radiative magnetohydrodynamic simulations of the solar atmosphere to carry out detailed tests of chromospheric diagnostics at millimeter and submillimeter wavelengths. Methods. We focused on the diagnostics of the thermal structure of the chromosphere in the wavelength bands from 0.4 mm up to 9.6 mm that can be accessed with the Atacama Large Millimeter/Submillimeter Array (ALMA) and investigated how these diagnostics are affected by the instrumental resolution. Results. We find that the formation height range of the millimeter radiation depends on the location in the simulation domain and is related to the underlying magnetic structure. Nonetheless, the brightness temperature is a reasonable measure of the gas temperature at the effective formation height at a given location on the solar surface. There is considerable scatter in this relationship, but this is significantly reduced when very weak magnetic fields are avoided. Our results indicate that although instrumental smearin...

  13. A Monte Carlo synthetic-acceleration method for solving the thermal radiation diffusion equation

    SciTech Connect (OSTI)

    Evans, Thomas M., E-mail: evanstm@ornl.gov [Oak Ridge National Laboratory, 1 Bethel Valley Rd., Oak Ridge, TN 37831 (United States); Mosher, Scott W., E-mail: moshersw@ornl.gov [Oak Ridge National Laboratory, 1 Bethel Valley Rd., Oak Ridge, TN 37831 (United States); Slattery, Stuart R., E-mail: sslattery@wisc.edu [University of Wisconsin–Madison, 1500 Engineering Dr., Madison, WI 53716 (United States); Hamilton, Steven P., E-mail: hamiltonsp@ornl.gov [Oak Ridge National Laboratory, 1 Bethel Valley Rd., Oak Ridge, TN 37831 (United States)

    2014-02-01T23:59:59.000Z

    We present a novel synthetic-acceleration-based Monte Carlo method for solving the equilibrium thermal radiation diffusion equation in three spatial dimensions. The algorithm performance is compared against traditional solution techniques using a Marshak benchmark problem and a more complex multiple material problem. Our results show that our Monte Carlo method is an effective solver for sparse matrix systems. For solutions converged to the same tolerance, it performs competitively with deterministic methods including preconditioned conjugate gradient and GMRES. We also discuss various aspects of preconditioning the method and its general applicability to broader classes of problems.

  14. A Monte Carlo Synthetic-Acceleration Method for Solving the Thermal Radiation Diffusion Equation

    SciTech Connect (OSTI)

    Evans, Thomas M [ORNL] [ORNL; Mosher, Scott W [ORNL] [ORNL; Slattery, Stuart [University of Wisconsin, Madison] [University of Wisconsin, Madison

    2014-01-01T23:59:59.000Z

    We present a novel synthetic-acceleration based Monte Carlo method for solving the equilibrium thermal radiation diusion equation in three dimensions. The algorithm performance is compared against traditional solution techniques using a Marshak benchmark problem and a more complex multiple material problem. Our results show that not only can our Monte Carlo method be an eective solver for sparse matrix systems, but also that it performs competitively with deterministic methods including preconditioned Conjugate Gradient while producing numerically identical results. We also discuss various aspects of preconditioning the method and its general applicability to broader classes of problems.

  15. Method and apparatus for thermal management of vehicle exhaust systems

    DOE Patents [OSTI]

    Benson, David K. (Golden, CO); Potter, Thomas F. (Denver, CO)

    1995-01-01T23:59:59.000Z

    A catalytic converter is surrounded by variable conductance insulation for maintaining the operating temperature of the catalytic converter at an optimum level, for inhibiting heat loss when raising catalytic converter temperature to light-off temperature, for storing excess heat to maintain or accelerate reaching light-off temperature, and for conducting excess heat away from the catalytic converter after reaching light-off temperature. The variable conductance insulation includes vacuum gas control and metal-to-metal thermal shunt mechanisms. Radial and axial shielding inhibits radiation and convection heat loss. Thermal storage media includes phase change material, and heat exchanger chambers and fluids carry heat to and from the catalytic converter.

  16. Numerical investigation of CO{sub 2} emission and thermal stability of a convective and radiative stockpile of reactive material in a cylindrical pipe of variable thermal conductivity

    SciTech Connect (OSTI)

    Lebelo, Ramoshweu Solomon, E-mail: sollyl@vut.ac.za [Department of Mathematics, Vaal University of Technology, Private Bag X021, Vanderbijlpark, 1911 (South Africa)

    2014-10-24T23:59:59.000Z

    In this paper the CO{sub 2} emission and thermal stability in a long cylindrical pipe of combustible reactive material with variable thermal conductivity are investigated. It is assumed that the cylindrical pipe loses heat by both convection and radiation at the surface. The nonlinear differential equations governing the problem are tackled numerically using Runge-Kutta-Fehlberg method coupled with shooting technique method. The effects of various thermophysical parameters on the temperature and carbon dioxide fields, together with critical conditions for thermal ignition are illustrated and discussed quantitatively.

  17. Compact vacuum insulation

    DOE Patents [OSTI]

    Benson, D.K.; Potter, T.F.

    1992-10-27T23:59:59.000Z

    Improved compact insulation panel is provided which is comprised of two adjacent metal sheets spaced close together with a plurality of spherical, or other discretely shaped, glass or ceramic beads optimally positioned between the sheets to provide support and maintain the spacing between the metal sheets when the gases there between are evacuated to form a vacuum. These spherical glass beads provide the maximum support while minimizing thermal conductance. In its preferred embodiment; these two metal sheets are textured with ribs or concave protrusions in conjunction with the glass beads to maximize the structural integrity of the panels while increasing the spacing between beads, thereby reducing the number of beads and the number of thermal conduction paths. Glass or porcelain-enameled liners in combination with the glass spacers and metal sidewalls effectively decrease thermal conductivity, and various laminates, including wood, porcelain-enameled metal, and others effectively increase the strength and insulation capabilities of the panels. Also, a metal web is provided to hold the spacers in place, and strategic grooves are shown to accommodate expansion and contraction or shaping of the panels. 35 figs.

  18. Compact vacuum insulation

    DOE Patents [OSTI]

    Benson, David K. (Golden, CO); Potter, Thomas F. (Denver, CO)

    1992-01-01T23:59:59.000Z

    Improved compact insulation panel is provided which is comprised of two adjacent metal sheets spaced close together with a plurality of spherical, or other discretely shaped, glass or ceramic beads optimally positioned between the sheets to provide support and maintain the spacing between the metal sheets when the gases therebetween are evacuated to form a vacuum. These spherical glass beads provide the maximum support while minimizing thermal conductance. In its preferred embodiment; these two metal sheets are textured with ribs or concave protrusions in conjunction with the glass beads to maximize the structural integrity of the panels while increasing the spacing between beads, thereby reducing the number of beads and the number of thermal conduction paths. Glass or porcelain-enameled liners in combination with the glass spacers and metal sidewalls effectively decrease thermal conductivity, and variious laminates, including wood, porcelain-enameled metal, and others effectively increase the strength and insulation capabilities of the panels. Also, a metal web is provided to hold the spacers in place, and strategic grooves are shown to accommodate expansion and contraction or shaping of the panels.

  19. Irradiation imposed degradation of the mechanical and electrical properties of electrical insulation for future accelerator magnets

    SciTech Connect (OSTI)

    Polinski, J.; Chorowski, M.; Bogdan, P.; Strychalski, M. [Wroclaw University of Technology, Wyb. Wyspianskiego 27, 50-370 Wroclaw (Poland); Rijk, G. de [European Organization for Nuclear Research CERN, 1211 Geneva (Switzerland)

    2014-01-27T23:59:59.000Z

    Future accelerators will make extensive use of superconductors made of Nb{sub 3}Sn, which allows higher magnetic fields than NbTi. However, the wind-and-react technology of Nb{sub 3}Sn superconducting magnet production makes polyimide Kapton® non applicable for the coils' electrical insulation. A Nb{sub 3}Sn technology compatible insulation material should be characterized by high radiation resistivity, good thermal conductivity, and excellent mechanical properties. Candidate materials for the electrical insulation of future accelerator's magnet coils have to be radiation certified with respect to potential degradation of their electrical, thermal, and mechanical properties. This contribution presents procedures and results of tests of the electrical and mechanical properties of DGEBA epoxy + D400 hardener, which is one of the candidates for the electrical insulation of future magnets. Two test sample types have been used to determine the material degradation due to irradiation: a untreated one (unirradiated) and irradiated at 77 K with 11 kGy/min intense, 4MeV energy electrons beam to a total dose of 50 MGy.

  20. Impact of Thermally Insulated Floors

    E-Print Network [OSTI]

    Alghimlas, F.; Omar, E. A.

    2004-01-01T23:59:59.000Z

    MODELLING INPUT The simulation period was set to be from January 1 until December 31. Typical meteorological year (TMY) was used for the coastal areas of Kuwait. The data were provided by KISR weather station at latitude of 29.3?C and longitude of 47....9?C [3]. Table 3 presents the TMY data in terms of monthly values of the significant weather parameters used within the simulation program. SIMULATION RESULTS AND ANALYSIS Private Villa The simulations were performed on four cases using...

  1. Radiation heat transfer in multitube, alkaline-metal thermal-to-electric converter

    SciTech Connect (OSTI)

    Tournier, J.M.P.; El-Genk, M.S. [Univ. of New Mexico, Albuquerque, NM (United States)

    1999-02-01T23:59:59.000Z

    Vapor anode, multitube Alkali-Metal Thermal-to-Electric Converters (AMTECs) are being considered for a number of space missions, such as the NASA Pluto/Express (PX) and Europa missions, scheduled for the years 2004 and 2005, respectively. These static converters can achieve a high fraction of Carnot efficiency at relatively low operating temperatures. An optimized cell can potentially provide a conversion efficiency between 20 and 30 percent, when operated at a hot-side temperature of 1000--1200 K and a cold-side temperature of 550--650 K. A comprehensive modeling and testing program of vapor anode, multitube AMTEC cells has been underway for more than three years at the Air Force Research Laboratory`s Power and Thermal Group (AFRL/VSDVP), jointly with the University of New Mexico`s Institute for Space and Nuclear Power Studies. The objective of this program is to demonstrate the readiness of AMTECs for flight on future US Air Force space missions. A fast, integrated AMTEC Performance and Evaluation Analysis Model (APEAM) has been developed to support ongoing vacuum tests at AFRL and perform analyses and investigate potential design changes to improve the PX-cell performance. This model consists of three major components (Tournier and El-Genk 1998a, b): (a) a sodium vapor pressure loss model, which describes continuum, transition and free-molecule flow regimes in the low-pressure cavity of the cell; (b) an electrochemical and electrical circuit model; and (c) a radiation/conduction heat transfer model, for calculating parasitic heat losses. This Technical Note describes the methodology used to calculate the radiation view factors within the enclosure of the PX-cells, and the numerical procedure developed in this work to determine the radiation heat transport and temperatures within the cell cavity.

  2. A Guide to Insulation Selection for Industrial Applications 

    E-Print Network [OSTI]

    Harrison, M. R.

    1979-01-01T23:59:59.000Z

    the system, degrade the insulation further and reduce the thermal effic iency. There is no question that rigid insulations such as calcium silicate are preferred in any application where abuse will occur. Some specifications call for all horizontal pip..., the owners are requiring more effic ient plant operations in both new and existing facilities. Thermal insulation will always playa major role in achieving those efficiencies, so its proper selection and application is of the utmost importance. 1012 ESL...

  3. Density Matrix Topological Insulators

    E-Print Network [OSTI]

    A. Rivas; O. Viyuela; M. A. Martin-Delgado

    2013-10-31T23:59:59.000Z

    Thermal noise can destroy topological insulators (TI). However we demonstrate how TIs can be made stable in dissipative systems. To that aim, we introduce the notion of band Liouvillian as the dissipative counterpart of band Hamiltonian, and show a method to evaluate the topological order of its steady state. This is based on a generalization of the Chern number valid for general mixed states (referred to as density matrix Chern value), which witnesses topological order in a system coupled to external noise. Additionally, we study its relation with the electrical conductivity at finite temperature, which is not a topological property. Nonetheless, the density matrix Chern value represents the part of the conductivity which is topological due to the presence of quantum mixed edge states at finite temperature. To make our formalism concrete, we apply these concepts to the two-dimensional Haldane model in the presence of thermal dissipation, but our results hold for arbitrary dimensions and density matrices.

  4. The Space Shuttle design presented many thermal insulation challenges. The system not only had to perform well, it had to integrate

    E-Print Network [OSTI]

    Steinetz Ice Detection Prevents Catastrophic Problems Charles Stevenson Aerogel-based Insulation System. In response, a coated carbon-carbon composite material was developed to Engineering Innovations 183 While. Since the surface acted as a catalyst, it was important that the interfacing material/coating have a low

  5. Topological insulators/Isolants topologiques An introduction to topological insulators

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Topological insulators/Isolants topologiques An introduction to topological insulators Introduction topology, the insulator is called a topological insulator. We introduce this notion of topological order sont finalement discutées. Keywords: topological insulator, topological band theory, quantum anomalous

  6. Irradiation requirements of Nb3Sn based SC magnets electrical insulation

    E-Print Network [OSTI]

    McDonald, Kirk

    Irradiation requirements of Nb3Sn based SC magnets electrical insulation developed within the Eu electrical insulation candidates · EuCARD insulators certification conditions · Post irradiation tests and neutrino factories will be subjected to very high radiation doses. · The electrical insulation employed

  7. On linearization and preconditioning for radiation diffusion coupled to material thermal conduction equations

    SciTech Connect (OSTI)

    Feng, Tao, E-mail: fengtao2@mail.ustc.edu.cn [School of Mathematical Sciences, University of Science and Technology of China, Hefei 230052 (China) [School of Mathematical Sciences, University of Science and Technology of China, Hefei 230052 (China); Graduate School of China Academy Engineering Physics, Beijing 100083 (China); An, Hengbin, E-mail: an_hengbin@iapcm.ac.cn [National Key Laboratory of Computational Physics, Institute of Applied Physics and Computational Mathematics, Beijing 100094 (China)] [National Key Laboratory of Computational Physics, Institute of Applied Physics and Computational Mathematics, Beijing 100094 (China); Yu, Xijun, E-mail: yuxj@iapcm.ac.cn [National Key Laboratory of Computational Physics, Institute of Applied Physics and Computational Mathematics, Beijing 100094 (China)] [National Key Laboratory of Computational Physics, Institute of Applied Physics and Computational Mathematics, Beijing 100094 (China); Li, Qin, E-mail: liqin@lsec.cc.ac.cn [Chinese Academy of Mathematics and Systems Science, Beijing 100190 (China)] [Chinese Academy of Mathematics and Systems Science, Beijing 100190 (China); Zhang, Rongpei, E-mail: zhangrongpei@163.com [Graduate School of China Academy Engineering Physics, Beijing 100083 (China)] [Graduate School of China Academy Engineering Physics, Beijing 100083 (China)

    2013-03-01T23:59:59.000Z

    Jacobian-free Newton–Krylov (JFNK) method is an effective algorithm for solving large scale nonlinear equations. One of the most important advantages of JFNK method is that there is no necessity to form and store the Jacobian matrix of the nonlinear system when JFNK method is employed. However, an approximation of the Jacobian is needed for the purpose of preconditioning. In this paper, JFNK method is employed to solve a class of non-equilibrium radiation diffusion coupled to material thermal conduction equations, and two preconditioners are designed by linearizing the equations in two methods. Numerical results show that the two preconditioning methods can improve the convergence behavior and efficiency of JFNK method.

  8. Enhancement of Topological Insulators Surface Conduction

    E-Print Network [OSTI]

    Yu, Xinxin

    2012-01-01T23:59:59.000Z

    Enhancement of Topological Insulators Surface Conduction AEnhancement of Topological Insulators Surface Conduction byTopological Insulator

  9. Multiple density layered insulator

    DOE Patents [OSTI]

    Alger, Terry W. (Tracy, CA)

    1994-01-01T23:59:59.000Z

    A multiple density layered insulator for use with a laser is disclosed wh provides at least two different insulation materials for a laser discharge tube, where the two insulation materials have different thermoconductivities. The multiple layer insulation materials provide for improved thermoconductivity capability for improved laser operation.

  10. Multiple density layered insulator

    DOE Patents [OSTI]

    Alger, T.W.

    1994-09-06T23:59:59.000Z

    A multiple density layered insulator for use with a laser is disclosed which provides at least two different insulation materials for a laser discharge tube, where the two insulation materials have different thermoconductivities. The multiple layer insulation materials provide for improved thermoconductivity capability for improved laser operation. 4 figs.

  11. Measure Guideline: Internal Insulation of Masonry Walls

    SciTech Connect (OSTI)

    Straube, J. F.; Ueno, K.; Schumacher, C. J.

    2012-07-01T23:59:59.000Z

    This measure guideline provides recommendations for interior insulation assemblies that control interstitial condensation and durability risks; recommendations for acceptable thermal performance are also provided. An illustrated guide of high-risk exterior details (which concentrate bulk water), and recommended remediation details is provided. This is followed by a recommended methodology for risk assessment of a masonry interior insulation project: a series of steps are suggested to assess the risks associated with this retrofit, with greater certainty with added steps.

  12. Radiation and thermal analysis of production solenoid for Mu2e experimental setup

    SciTech Connect (OSTI)

    Pronskikh, V.S.; Kashikhin, V.V.; Mokhov, N.V.; /Fermilab

    2011-03-01T23:59:59.000Z

    The Muon-to-Electron (Mu2e) experiment at Fermilab, will seek the evidence of direct muon to electron conversion at the sensitivity level where it cannot be explained by the Standard Model. An 8-GeV 25-kW proton beam will be directed onto a tilted gold target inside a large-bore superconducting Production Solenoid (PS) with the peak field on the axis of {approx}5T. The negative muons resulting from the pion decay will be captured in the PS aperture and directed by an S-shaped Transport Solenoid towards the stopping target inside the Detector Solenoid. In order for the superconducting magnets to operate reliably and with a sufficient safety margin, the peak neutron flux entering the coils must be reduced by 3 orders of magnitude that is achieved by means of a sophisticated absorber placed in the magnet aperture. The proposed absorber, consisting of W- and Cu-based alloy parts, is optimized for the performance and cost. Results of MARS15 simulations of energy deposition and radiation are reported. The results of the PS magnet thermal analysis, coordinated with the coil cooling scheme, are reported as well for the selected absorber design.

  13. Compact gas-insulated transformer. Fourteenth quarterly report

    SciTech Connect (OSTI)

    Not Available

    1983-08-01T23:59:59.000Z

    Objective is to develop a compact, more efficient, quieter transformer which does not rely on mineral oil insulation. Compressed SF/sub 6/ is used as the external insulation and polymer film as the insulation between turns. A separate liquid cooling system is also provided. This document reports progress made in design, mechanical, dielectric, short circuit, thermal, materials, prototype, accessories, commercialization, and system studies. (DLC)

  14. Thermal properties of organic and inorganic aerogels

    SciTech Connect (OSTI)

    Hrubesh, L.W.; Pekala, R.W. (Chemistry and Material Science Department, Lawrence Livermore National Laboratory, Livermore, California 94551-9900 (United States))

    1994-03-01T23:59:59.000Z

    Aerogels are open-cell foams that have already been shown to be among the best thermal insulating solid materials known. This paper examines the three major contributions to thermal transport through porous materials; solid, gaseous, and radiative, to identify how to reduce the thermal conductivity of air-filled aerogels. We find that significant improvements in the thermal insulation property of aerogels are possible by; (i) employing materials with a low intrinsic solid conductivity, (ii) reducing the average pore size within aerogels, and (iii) affecting an increase of the infrared extinction in aerogels. Theoretically, polystyrene is the best of the organic materials and zirconia is the best inorganic material to use for the lowest achievable conductivity. Significant reduction of the thermal conductivity for all aerogel varieties is predicted with only a modest decrease of the average pore size. This might be achieved by modifying the sol-gel chemistry leading to aerogels. For example, a thermal resistance value of [ital R]=20 per inch would be possible for an air-filled resorcinol-formaldehyde aerogel at a density of 156 kg/m[sup 3], if the average pore size was less than 35 nm. An equation is included which facilitates the calculation of the optimum density for the minimum total thermal conductivity, for all varieties of aerogels.

  15. Vacuum-insulated catalytic converter

    DOE Patents [OSTI]

    Benson, David K. (Golden, CO)

    2001-01-01T23:59:59.000Z

    A catalytic converter has an inner canister that contains catalyst-coated substrates and an outer canister that encloses an annular, variable vacuum insulation chamber surrounding the inner canister. An annular tank containing phase-change material for heat storage and release is positioned in the variable vacuum insulation chamber a distance spaced part from the inner canister. A reversible hydrogen getter in the variable vacuum insulation chamber, preferably on a surface of the heat storage tank, releases hydrogen into the variable vacuum insulation chamber to conduct heat when the phase-change material is hot and absorbs the hydrogen to limit heat transfer to radiation when the phase-change material is cool. A porous zeolite trap in the inner canister absorbs and retains hydrocarbons from the exhaust gases when the catalyst-coated substrates and zeolite trap are cold and releases the hydrocarbons for reaction on the catalyst-coated substrate when the zeolite trap and catalyst-coated substrate get hot.

  16. Membranes Improve Insulation Efficiency

    E-Print Network [OSTI]

    Bullock, C. A.

    1986-01-01T23:59:59.000Z

    No Clear White Alum Temp Mem Mem Mem Foil FIGURE 7 Temperature Inside Room and Temperature Next to Top of Sheetrock Under Various insulation Configurations. It should be noted that after this test was completed, the fiber insulation was inspected...

  17. Insulating polymer concrete

    DOE Patents [OSTI]

    Schorr, H. Peter (Douglaston, NY); Fontana, Jack J. (Shirley, NY); Steinberg, Meyer (Melville, NY)

    1987-01-01T23:59:59.000Z

    A lightweight insulating polymer concrete formed from a lightweight closed cell aggregate and a water resistance polymeric binder.

  18. Topological Insulators & Superconductors

    E-Print Network [OSTI]

    Topological Insulators & Superconductors New Frontiers in Low-Dimensional Systems Program 3-5 November 2010 Jadwin Hall, Fourth Floor, Room 407 Topological Insulators and Superconductors have quickly Insulators and Superconductors will gather the world- leading researchers in this field to present recent

  19. High temperature structural insulating material

    DOE Patents [OSTI]

    Chen, W.Y.

    1984-07-27T23:59:59.000Z

    A high temperature structural insulating material useful as a liner for cylinders of high temperature engines through the favorable combination of high service temperature (above about 800/sup 0/C), low thermal conductivity (below about 0.2 W/m/sup 0/C), and high compressive strength (above about 250 psi). The insulating material is produced by selecting hollow ceramic beads with a softening temperature above about 800/sup 0/C, a diameter within the range of 20-200 ..mu..m, and a wall thickness in the range of about 2 to 4 ..mu..m; compacting the beads and a compatible silicate binder composition under pressure and sintering conditions to provide the desired structural form with the structure having a closed-cell, compact array of bonded beads.

  20. High temperature structural insulating material

    DOE Patents [OSTI]

    Chen, Wayne Y. (Munster, IN)

    1987-01-01T23:59:59.000Z

    A high temperature structural insulating material useful as a liner for cylinders of high temperature engines through the favorable combination of high service temperature (above about 800.degree. C.), low thermal conductivity (below about 0.2 W/m.degree. C.), and high compressive strength (above about 250 psi). The insulating material is produced by selecting hollow ceramic beads with a softening temperature above about 800.degree. C., a diameter within the range of 20-200 .mu.m, and a wall thickness in the range of about 2-4 .mu.m; compacting the beads and a compatible silicate binder composition under pressure and sintering conditions to provide the desired structural form with the structure having a closed-cell, compact array of bonded beads.

  1. Multilayer insulation blanket, fabricating apparatus and method

    DOE Patents [OSTI]

    Gonczy, John D. (Oak Lawn, IL); Niemann, Ralph C. (Downers Grove, IL); Boroski, William N. (Aurora, IL)

    1992-01-01T23:59:59.000Z

    An improved multilayer insulation blanket for insulating cryogenic structures operating at very low temperatures is disclosed. An apparatus and method for fabricating the improved blanket are also disclosed. In the improved blanket, each successive layer of insulating material is greater in length and width than the preceding layer so as to accommodate thermal contraction of the layers closest to the cryogenic structure. The fabricating apparatus has a rotatable cylindrical mandrel having an outer surface of fixed radius that is substantially arcuate, preferably convex, in cross-section. The method of fabricating the improved blanket comprises (a) winding a continuous sheet of thermally reflective material around the circumference of the mandrel to form multiple layers, (b) binding the layers along two lines substantially parallel to the edges of the circumference of the mandrel, (c) cutting the layers along a line parallel to the axle of the mandrel, and (d) removing the bound layers from the mandrel.

  2. Method of fabricating a multilayer insulation blanket

    DOE Patents [OSTI]

    Gonczy, John D. (Oak Lawn, IL); Niemann, Ralph C. (Downers Grove, IL); Boroski, William N. (Aurora, IL)

    1993-01-01T23:59:59.000Z

    An improved multilayer insulation blanket for insulating cryogenic structures operating at very low temperatures is disclosed. An apparatus and method for fabricating the improved blanket are also disclosed. In the improved blanket, each successive layer of insulating material is greater in length and width than the preceding layer so as to accommodate thermal contraction of the layers closest to the cryogenic structure. The fabricating apparatus has a rotatable cylindrical mandrel having an outer surface of fixed radius that is substantially arcuate, preferably convex, in cross-section. The method of fabricating the improved blanket comprises (a) winding a continuous sheet of thermally reflective material around the circumference of the mandrel to form multiple layers, (b) binding the layers along two lines substantially parallel to the edges of the circumference of the mandrel, (c) cutting the layers along a line parallel to the axle of the mandrel, and (d) removing the bound layers from the mandrel.

  3. Continental insulation, mantle cooling, and the surface area of oceans and continents

    E-Print Network [OSTI]

    Manga, Michael

    Continental insulation, mantle cooling, and the surface area of oceans and continents A. Lenardica May 2005 Abstract It is generally assumed that continents, acting as thermal insulation above. The theory predicts that parameter regimes exist for which increased continental insulation has no effect

  4. aerogel thermal isolation: Topics by E-print Network

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

    interstitial layers; Isolation of heat affected regions with thermal insulation--aerogels; Dissipation of unwanted thermal energy through efficient heat transfer--heat...

  5. Enhancing VHTR Passive Safety and Economy with Thermal Radiation Based Direct Reactor Auxiliary Cooling System

    SciTech Connect (OSTI)

    Haihua Zhao; Hongbin Zhang; Ling Zou; Xiaodong Sun

    2012-06-01T23:59:59.000Z

    One of the most important requirements for Gen. IV Very High Temperature Reactor (VHTR) is passive safety. Currently all the gas cooled version of VHTR designs use Reactor Vessel Auxiliary Cooling System (RVACS) for passive decay heat removal. The decay heat first is transferred to the core barrel by conduction and radiation, and then to the reactor vessel by thermal radiation and convection; finally the decay heat is transferred to natural circulated air or water systems. RVACS can be characterized as a surface based decay heat removal system. The RVACS is especially suitable for smaller power reactors since small systems have relatively larger surface area to volume ratio. However, RVACS limits the maximum achievable power level for modular VHTRs due to the mismatch between the reactor power (proportional to volume) and decay heat removal capability (proportional to surface area). When the relative decay heat removal capability decreases, the peak fuel temperature increases, even close to the design limit. Annular core designs with inner graphite reflector can mitigate this effect; therefore can further increase the reactor power. Another way to increase the reactor power is to increase power density. However, the reactor power is also limited by the decay heat removal capability. Besides the safety considerations, VHTRs also need to be economical in order to compete with other reactor concepts and other types of energy sources. The limit of decay heat removal capability set by using RVACS has affected the economy of VHTRs. A potential alternative solution is to use a volume-based passive decay heat removal system, called Direct Reactor Auxiliary Cooling Systems (DRACS), to remove or mitigate the limitation on decay heat removal capability. DRACS composes of natural circulation loops with two sets of heat exchangers, one on the reactor side and another on the environment side. For the reactor side, cooling pipes will be inserted into holes made in the outer or inner graphite reflector blocks. There will be gaps between these cooling pipes and their corresponding surrounding graphite surfaces. Graphite has an excellent heat conduction property. By taking advantage of this feature, we can have a volume-based method to remove decay heat. The scalability can be achieved, if needed, by employing more rows of cooling pipes to accommodate higher decay heat rates. Since heat can easily conduct through the graphite regions between the holes made for the cooling pipes, those cooling pipes located further away from the active core region can still be very effective in removing decay heat. By removing the limit on the decay heat removal capability due to the limited available surface area as in a RVACS, the reactor power and power density can be significantly increased, without losing the passive heat removal feature. This paper will introduce the concept of using DRACS to enhance VHTR passive safety and economics. Three design options will be discussed, depending on the cooling pipe locations. Analysis results from a lumped volume based model and CFD simulations will be presented.

  6. Laminated insulators having heat dissipation means

    DOE Patents [OSTI]

    Niemann, R.C.; Mataya, K.F.; Gonczy, J.D.

    1980-04-24T23:59:59.000Z

    A laminated body is provided with heat dissipation capabilities. The insulator body is formed by dielectric layers interleaved with heat conductive layers, and bonded by an adhesive to form a composite structure. The heat conductive layers include provision for connection to an external thermal circuit.

  7. On the oxidation of high-temperature alloys, and its role in failure of thermal barrier coatings

    E-Print Network [OSTI]

    Loeffel, Kaspar Andreas

    2013-01-01T23:59:59.000Z

    Thermal barrier coating (TBC) systems are applied to superalloy turbine blades to provide thermal insulation and oxidation protection. A TBC system consists of (a) an outer oxide layer that imparts thermal insulation, and ...

  8. Sheath insulator final test report, TFE Verification Program

    SciTech Connect (OSTI)

    Not Available

    1994-07-01T23:59:59.000Z

    The sheath insulator in a thermionic cell has two functions. First, the sheath insulator must electrically isolate the collector form the outer containment sheath tube that is in contact with the reactor liquid metal coolant. Second, The sheath insulator must provide for high uniform thermal conductance between the collector and the reactor coolant to remove away waste heat. The goals of the sheath insulator test program were to demonstrate that suitable ceramic materials and fabrication processes were available, and to validate the performance of the sheath insulator for TFE-VP requirements. This report discusses the objectives of the test program, fabrication development, ex-reactor test program, in-reactor test program, and the insulator seal specifications.

  9. Thermal stress analysis of eccentric tube receiver using concentrated solar radiation

    SciTech Connect (OSTI)

    Wang, Fuqiang; Shuai, Yong; Yuan, Yuan; Yang, Guo; Tan, Heping [School of Energy Science and Engineering, Harbin Institute of Technology, 92, West Dazhi Street, Harbin 150001 (China)

    2010-10-15T23:59:59.000Z

    In the parabolic trough concentrator with tube receiver system, the heat transfer fluid flowing through the tube receiver can induce high thermal stress and deflection. In this study, the eccentric tube receiver is introduced with the aim to reduce the thermal stresses of tube receiver. The ray-thermal-structural sequential coupled numerical analyses are adopted to obtain the concentrated heat flux distributions, temperature distributions and thermal stress fields of both the eccentric and concentric tube receivers. During the sequential coupled numerical analyses, the concentrated heat flux distribution on the bottom half periphery of tube receiver is obtained by Monte-Carlo ray tracing method, and the fitting function method is introduced for the calculated heat flux distribution transformation from the Monte-Carlo ray tracing model to the CFD analysis model. The temperature distributions and thermal stress fields are obtained by the CFD and FEA analyses, respectively. The effects of eccentricity and oriented angle variation on the thermal stresses of eccentric tube receiver are also investigated. It is recommended to adopt the eccentric tube receiver with optimum eccentricity and 90 oriented angle as tube receiver for the parabolic trough concentrator system to reduce the thermal stresses. (author)

  10. Radiative component and combined heat transfer in the thermal calculation of finned tube banks

    SciTech Connect (OSTI)

    Stehlik, P. [Technical Univ. of Brno (Czech Republic). Dept. of Process Engineering] [Technical Univ. of Brno (Czech Republic). Dept. of Process Engineering

    1999-01-01T23:59:59.000Z

    For more exact calculation of combined heat transfer in the case of finned tube banks (e.g., in the convective section of a furnace), the radiative heat transfer cannot be neglected. A new method for relatively simple calculation of total heat flux (convection + radiation + conduction in fins) is fully compatible with that for bare tube banks/bundles developed earlier. It is based on the method of radiative coefficients. However, the resulting value of heat flux must be corrected due to fin thickness and especially due to the fin radiative influence. For this purpose the so-called multiplicator of heat flux was introduced. The applicability of this methods has been demonstrated on a tubular fired heater convective section. A developed computer program based on the method has also been used for an analysis of the influence of selected parameters to show the share of radiation on the total heat flux.

  11. Correctly specify insulation for process equipment and piping

    SciTech Connect (OSTI)

    Allen, C. [Raytheon Engineers and Constructors, Birmingham, AL (United States)

    1997-05-01T23:59:59.000Z

    Insulation serves as a thermal barrier to resist the flow of heat. When insulation is installed over piping or equipment to minimize heat losses, the insulation is categorized as heat conservation. Software programs for determining heat losses are based on ASTM C 680. If heat conservation insulation is calculated to determine the most cost-effective thickness for piping or equipment, then the insulation is categorized as economic insulation. Methods for manually determining economic thicknesses using various graphs and precalculated charts are given in Turner and Malloy. However, modern software programs available from industrial associations calculate economic thicknesses based on after-tax annual costs. Costs associated with owning insulation are expressed on an equivalent uniform annual cost basis. The thickness with the lowest annual cost is reported as the economic thickness. Some of the economic data needed to calculate economic thicknesses are fuel cost, depreciation period, annual fuel inflation rate, annual hours of operation, return on investment, effective income tax rate, annual insulation maintenance costs, and installed costs. To obtain accurate economical thicknesses, it is best to solicit installed costs from a local contractor likely to bid on the work. This paper covers the most suitable insulation materials for certain applications, the most economic material and thickness to use, and how the total insulation system should be designed.

  12. Magnetic-field control of near-field radiative heat transfer and the realization of highly tunable hyperbolic thermal emitters

    E-Print Network [OSTI]

    Moncada-Villa, Edwin; Garcia-Vidal, Francisco J; Garcia-Martin, Antonio; Cuevas, Juan Carlos

    2015-01-01T23:59:59.000Z

    We present a comprehensive theoretical study of the magnetic field dependence of the near-field radiative heat transfer (NFRHT) between two parallel plates. We show that when the plates are made of doped semiconductors, the near-field thermal radiation can be severely affected by the application of a static magnetic field. We find that irrespective of its direction, the presence of a magnetic field reduces the radiative heat conductance, and dramatic reductions up to 700% can be found with fields of about 6 T at room temperature. We show that this striking behavior is due to the fact that the magnetic field radically changes the nature of the NFRHT. The field not only affects the electromagnetic surface waves (both plasmons and phonon polaritons) that normally dominate the near-field radiation in doped semiconductors, but it also induces hyperbolic modes that progressively dominate the heat transfer as the field increases. In particular, we show that when the field is perpendicular to the plates, the semicond...

  13. A Simple Holographic Insulator

    E-Print Network [OSTI]

    Eric Mefford; Gary T. Horowitz

    2014-07-11T23:59:59.000Z

    We present a simple holographic model of an insulator. Unlike most previous holographic insulators, the zero temperature infrared geometry is completely nonsingular. Both the low temperature DC conductivity and the optical conductivity at zero temperature satisfy power laws with the same exponent, given by the scaling dimension of an operator in the IR. Changing a parameter in the model converts it from an insulator to a conductor with a standard Drude peak.

  14. Pipe Insulation Economies

    E-Print Network [OSTI]

    Schilling, R. E.

    PIPE INSULATION ECONOMIES Robert E. Schilling, P.E. Eaton Corporation Aurora, Ohio ABSTRACT Pipe Insulation Economies is a computer pro gram written in IBM basic to simplify the economic insulation thickness for an insulated pipe. Many... ECONOMIES" 30 LOCATE 10,29:PRINT"ROBERT E. SCHILLING,P.E." 40 LOCATE l2,3l:PRINT"EATON CORPORATION" 50 LOCATE l3,26:PRINT"119 Q SOUTH CHILLICOTHE ROAD" 598 ESL-IE-86-06-97 Proceedings from the Eighth Annual Industrial Energy Technology Conference...

  15. INSTALLATION CERTIFICATE CF-6R-ENV-01 Envelope Insulation; Roofing; Fenestration (Page 1 of 3)

    E-Print Network [OSTI]

    INSTALLATION CERTIFICATE CF-6R-ENV-01 Envelope ­ Insulation; Roofing; Fenestration (Page 1 of 3:__________________________________ Brand Name:_______________________________ Thickness (inches):_________________________ Thermal:_______________________________ Thickness (inches):_________________________ Thermal Resistance (R-Value):_________________ Perimeter

  16. Experimental methodology for non-thermal effects of electromagnetic radiation on biologics

    E-Print Network [OSTI]

    Cox, Felicia C. A. I

    2006-01-01T23:59:59.000Z

    Appropriate equipment is needed for research on the effects of radio-frequency radiation from radio-frequency identification (RF-ID) systems on biological materials. In the present study, a complete test system comprising ...

  17. Apparatus for insulating windows and the like

    DOE Patents [OSTI]

    Mitchell, R.A.

    1984-06-19T23:59:59.000Z

    Apparatus for insulating window openings through walls and the like includes a thermal shutter, a rail for mounting the shutter adjacent to the window opening and a coupling for connecting the shutter to the rail. The thermal shutter includes an insulated panel adhered to frame members which surround the periphery of the panel. The frame members include a hard portion for providing the frame and a soft portion for providing a seal with that portion of the wall adjacent to the periphery of the opening. The coupling means is preferably integral with the attachment rail. According to a preferred embodiment, the coupling means includes a continuous hinge of reduced thickness. The thermal shutter can be permanently attached, hinged, bi-folded, or sliding with respect to the window and wall. A distribution method is to market the apparatus in kit'' form. 11 figs.

  18. Apparatus for insulating windows and the like

    DOE Patents [OSTI]

    Mitchell, Robert A. (R.D. #1, Box 462-A, Voorheesville, NY 12186)

    1984-01-01T23:59:59.000Z

    Apparatus for insulating window openings through walls and the like includes a thermal shutter, a rail for mounting the shutter adjacent to the window opening and a coupling for connecting the shutter to the rail. The thermal shutter includes an insulated panel adhered to frame members which surround the periphery of the panel. The frame members include a hard portion for providing the frame and a soft portion for providing a seal with that portion of the wall adjacent to the periphery of the opening. The coupling means is preferably integral with the attachment rail. According to a preferred embodiment, the coupling means includes a continuous hinge of reduced thickness. The thermal shutter can be permanently attached, hinged, bi-folded, or sliding with respect to the window and wall. A distribution method is to market the apparatus in "kit" form.

  19. CALIFORNIA ENERGY Ceiling Insulation Report

    E-Print Network [OSTI]

    CALIFORNIA ENERGY COMMISSION Ceiling Insulation Report: Effectiveness of Lay-In Ceiling Insulation Effectiveness of Lay-In Insulation (product 5.2.6) TECHNICALREPORT October 2003 500-03-082-A-14 Gray Davis

  20. Analysis and testing of multilayer and aerogel insulation configurations

    SciTech Connect (OSTI)

    Johnson, W L [NASA Kennedy Space Center, Kennedy Space Center, Florida; Demko, Jonathan A [ORNL; Fesmire, J. E. [NASA Kennedy Space Center, Kennedy Space Center, Florida

    2010-01-01T23:59:59.000Z

    Multilayer insulation systems that have robust operational characteristics have long been a goal of many research projects. Such thermal insulation systems may need to offer some degree of structural support and/or mechanical integrity during loss of vacuum scenarios while continuing to provide insulative value to the vessel. Aerogel-based composite blankets can be the best insulation materials in ambient pressure environments; in high vacuum, the thermal performance of aerogel improves by about one order of magnitude. Standard multilayer insulation (MLI) is typically 50% worse at ambient pressure and at soft vacuum, but as much as two or three orders of magnitude better at high vacuum. Different combinations of aerogel blanket and multilayer insulation materials have been tested at the Cryogenics Test Laboratory of NASA Kennedy Space Center. Analysis performed at Oak Ridge National Laboratory showed an importance to the relative location of the MLI and aerogel blankets. Apparent thermal conductivity testing under cryogenicvacuum conditions was performed to verify the analytical conclusion. Tests results are shown to be in agreement with the analysis which indicated that the best performance is obtained with aerogel layers located in the middle of the blanket insulation system.

  1. Thermal unobtainiums? The perfect thermal conductor and

    E-Print Network [OSTI]

    Braun, Paul

    conduction · Heat conduction in Bose condensates ­ electronic superconductors ­ superfluid helium ­ Bose condensate of magnons #12;Outline--toward perfect thermal insulators · Einstein and minimum thermal directions #12;Gas kinetic equation is a good place to start · Anharmonicity (high T limit) · Point defect

  2. Electrical insulator assembly with oxygen permeation barrier

    DOE Patents [OSTI]

    Van Der Beck, Roland R. (Lansdale, PA); Bond, James A. (Exton, PA)

    1994-01-01T23:59:59.000Z

    A high-voltage electrical insulator (21) for electrically insulating a thermoelectric module (17) in a spacecraft from a niobium-1% zirconium alloy wall (11) of a heat exchanger (13) filled with liquid lithium (16) while providing good thermal conductivity between the heat exchanger and the thermoelectric module. The insulator (21) has a single crystal alumina layer (SxAl.sub.2 O.sub.3, sapphire) with a niobium foil layer (32) bonded thereto on the surface of the alumina crystal (26) facing the heat exchanger wall (11), and a molybdenum layer (31) bonded to the niobium layer (32) to act as an oxygen permeation barrier to preclude the oxygen depleting effects of the lithium from causing undesirable niobium-aluminum intermetallic layers near the alumina-niobium interface.

  3. Electrical insulator assembly with oxygen permeation barrier

    DOE Patents [OSTI]

    Van Der Beck, R.R.; Bond, J.A.

    1994-03-29T23:59:59.000Z

    A high-voltage electrical insulator for electrically insulating a thermoelectric module in a spacecraft from a niobium-1% zirconium alloy wall of a heat exchanger filled with liquid lithium while providing good thermal conductivity between the heat exchanger and the thermoelectric module. The insulator has a single crystal alumina layer (SxAl[sub 2]O[sub 3], sapphire) with a niobium foil layer bonded thereto on the surface of the alumina crystal facing the heat exchanger wall, and a molybdenum layer bonded to the niobium layer to act as an oxygen permeation barrier to preclude the oxygen depleting effects of the lithium from causing undesirable niobium-aluminum intermetallic layers near the alumina-niobium interface. 3 figures.

  4. Method and apparatus for thermal management of vehicle exhaust systems

    DOE Patents [OSTI]

    Benson, D.K.; Potter, T.F.

    1995-12-26T23:59:59.000Z

    A catalytic converter is surrounded by variable conductance insulation for maintaining the operating temperature of the catalytic converter at an optimum level, for inhibiting heat loss when raising catalytic converter temperature to light-off temperature, for storing excess heat to maintain or accelerate reaching light-off temperature, and for conducting excess heat away from the catalytic converter after reaching light-off temperature. The variable conductance insulation includes vacuum gas control and metal-to-metal thermal shunt mechanisms. Radial and axial shielding inhibits radiation and convection heat loss. Thermal storage media includes phase change material, and heat exchanger chambers and fluids carry heat to and from the catalytic converter. 7 figs.

  5. Impact of the Position of a Radiator to Energy Consumption and Thermal Comfort in a Mixed Radiant and Convective Heating System

    E-Print Network [OSTI]

    Gong, X.; Claridge, D. E.

    2005-01-01T23:59:59.000Z

    ESL-IC-10/05-35 1 Impact of the Position of the Radiator on Energy Consumption and Thermal Comfort in a Mixed Radiant and Convective Heating System Xiangyang Gong David E... the energy consumption and thermal comfort distribution in a typical office with a mixed radiant and convective heating system for two different locations of radiant heat sources. Accurately estimating the energy consumption in a mixed heating space...

  6. Impact of the Position of a Radiator to Energy Consumption and Thermal Comfort in a Mixed Radiant and Convective Heating System 

    E-Print Network [OSTI]

    Gong, X.; Claridge, D. E.

    2005-01-01T23:59:59.000Z

    ESL-IC-10/05-35 1 Impact of the Position of the Radiator on Energy Consumption and Thermal Comfort in a Mixed Radiant and Convective Heating System Xiangyang Gong David E... the energy consumption and thermal comfort distribution in a typical office with a mixed radiant and convective heating system for two different locations of radiant heat sources. Accurately estimating the energy consumption in a mixed heating space...

  7. Radiated power measurement during the thermal quench phase of a density limit disruption

    E-Print Network [OSTI]

    California at San Diego, University of

    , but is believed to conduct preferentially to the divertor plates.4,5 In future reactor-size tokamaks, where stored of highly radiating impurities usually a noble gas such as neon , either through a massive gas puff11 to affect the plasma after being triggered and are therefore not fast enough to mitigate the entire dis

  8. Non-thermal radiation from single O stars Sven Van Loo

    E-Print Network [OSTI]

    Van Loo, Sven

    the width of the spectral line. This line satu- ration reduces the effectiveness of line driving. An extra ingredient must be taken into account for line driving to be effective: Doppler sweeping of the lines of spectral type O have very strong stellar winds, driven by the line-scattering of stellar radiation. Besides

  9. Cooper-Pair Injection into Topological Insulators and Helical Wires

    E-Print Network [OSTI]

    Sato, Koji

    2013-01-01T23:59:59.000Z

    Topological Insulator . . . . . . . . . . . . . . . . . . . . . . . .phenomena : Topological Insulators and Superconductors. ”Colloquium : Topological insulators. ” Rev. Mod. Phys. , 82:

  10. Classical Gluon Radiation in Ultrarelativistic Nuclear Collisions: Space-Time Structure, Instabilities, and Thermalization

    E-Print Network [OSTI]

    S. G. Matinyan; B. Mueller; D. H. Rischke

    1997-08-28T23:59:59.000Z

    We investigate the space-time structure of the classical gluon field produced in an ultrarelativistic collision between color charges. The classical solution which was computed previously in a perturbative approach is shown to become unstable on account of the non-Abelian self-interaction neglected in the perturbative solution scheme. The time scale for growth of the instabilities is found to be of the order of the distance between the colliding color charges. We argue that these instabilities will eventually lead to thermalization of gluons produced in an ultrarelativistic collision between heavy nuclei. The rate of thermalization is estimated to be of order $g^2 \\mu$, where $g$ is the strong coupling constant and $\\mu^2$ the transverse color charge density of an ultrarelativistic nucleus.

  11. Probing the thermal character of analogue Hawking radiation for shallow water waves?

    E-Print Network [OSTI]

    Florent Michel; Renaud Parentani

    2014-09-15T23:59:59.000Z

    We study and numerically compute the scattering coefficients of shallow water waves blocked by a stationary counterflow. When the flow is transcritical, the coefficients closely follow Hawking's prediction according to which black holes should emit a thermal spectrum. We study how the spectrum deviates from thermality when reducing the maximal flow velocity, with a particular attention to subcritical flows since these have been recently used to test Hawking's prediction. For such flows, we show that the emission spectrum is strongly suppressed, and that its Planckian character is completely lost. For low frequencies, we also show that the scattering coefficients are dominated by elastic hydrodynamical channels. Our numerical results reproduce rather well the observations made by S. Weinfurtner {\\it et al.} in the Vancouver experiment. Nevertheless, we propose a new interpretation of what has been observed, as well as new experimental tests.

  12. Exterior Insulation Finish System (EIFS) Walls ORNL provides the tools to enable industry to engineer durable, moisture-tolerant

    E-Print Network [OSTI]

    Oak Ridge National Laboratory

    Exterior Insulation Finish System (EIFS) Walls ORNL provides the tools to enable industry the insulating value of walls and the energy efficiency of buildings. The EIFS concept came to America from in both moisture control and insulating value. EIFS's are inherently superior on thermal performance

  13. Aerogel-Based Insulation for Industrial Steam Distribution Systems

    SciTech Connect (OSTI)

    John Williams

    2011-03-30T23:59:59.000Z

    Thermal losses in industrial steam distribution systems account for 977 trillion Btu/year in the US, more than 1% of total domestic energy consumption. Aspen Aerogels worked with Department of Energy’s Industrial Technologies Program to specify, develop, scale-up, demonstrate, and deliver Pyrogel XT®, an aerogel-based pipe insulation, to market to reduce energy losses in industrial steam systems. The product developed has become Aspen’s best selling flexible aerogel blanket insulation and has led to over 60 new jobs. Additionally, this product has delivered more than ~0.7 TBTU of domestic energy savings to date, and could produce annual energy savings of 149 TBTU by 2030. Pyrogel XT’s commercial success has been driven by it’s 2-4X better thermal performance, improved durability, greater resistance to corrosion under insulation (CUI), and faster installation times than incumbent insulation materials.

  14. Radiative neutron capture on 9be, 14c, 14n, 15n and 16o at thermal and astrophysical energies

    E-Print Network [OSTI]

    Sergey Dubovichenko; Albert Dzhazairov-Kakhramanov; Nadezhda Afanasyeva

    2014-01-28T23:59:59.000Z

    The total cross sections of the radiative neutron capture processes on 9Be, 14C, 14N, 15N, and 16O are described in the framework of the modified potential cluster model with the classification of orbital states according to Young tableaux. The continued interest in the study of these reactions is due, on the one hand, to the important role played by this process in the analysis of many fundamental properties of nuclei and nuclear reactions, and, on the other hand, to the wide use of the capture cross section data in the various applications of nuclear physics and nuclear astrophysics, and, also, to the importance of the analysis of primordial nucleosynthesis in the Universe. This article is devoted to the description of results for the processes of the radiative neutron capture on certain light atomic nuclei at thermal and astrophysical energies. The considered capture reactions are not part of stellar thermonuclear cycles, but involve in the reaction chains of inhomogeneous Big Bang models.

  15. Cooper Pairs in Insulators?!

    ScienceCinema (OSTI)

    James Valles

    2010-01-08T23:59:59.000Z

    Nearly 50 years elapsed between the discovery of superconductivity and the emergence of the microscopic theory describing this zero resistance state. The explanation required a novel phase of matter in which conduction electrons joined in weakly bound pairs and condensed with other pairs into a single quantum state. Surprisingly, this Cooper pair formation has also been invoked to account for recently uncovered high-resistance or insulating phases of matter. To address this possibility, we have used nanotechnology to create an insulating system that we can probe directly for Cooper pairs. I will present the evidence that Cooper pairs exist and dominate the electrical transport in these insulators and I will discuss how these findings provide new insight into superconductor to insulator quantum phase transitions. 

  16. Normal shock solutions to the viscous shock layer equations including thermal, chemical, thermodynamic, and radiative nonequilibrium

    E-Print Network [OSTI]

    Mott, David Ray

    1993-01-01T23:59:59.000Z

    term (Eq. (12)) density relaxation time inelastic energy exchange term (Eq. (12)) Subscripts and Superscripts b b c cal e f 1 i initial J P r s tr v V backward reaction boundary center, as in X, calibration constant electron... such experiments vital in the verification of nonequilibrium chemical and radiation models. PUMPING ASSEMBLT CDAxIAL CABLE HousING L ? --I r- 2sTDPFARAb )'V& DRIVER HIGHPRESSURE DIAPHRAGM TRANSITION SECTION Cl~ ALUMINUM TUBE TUBE t2OFTI TUBE I 10 F...

  17. Near-field thermal radiation between hyperbolic metamaterials: Graphite and carbon nanotubes

    SciTech Connect (OSTI)

    Liu, X. L.; Zhang, R. Z.; Zhang, Z. M., E-mail: zhuomin.zhang@me.gatech.edu [G. W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States)

    2013-11-18T23:59:59.000Z

    The near-field radiative heat transfer for two hyperbolic metamaterials, namely, graphite and vertically aligned carbon nanotubes (CNTs), is investigated. Graphite is a naturally existing uniaxial medium, while CNT arrays can be modeled as an effective anisotropic medium. Different hyperbolic modes can be separately supported by these materials in certain infrared regions, resulting in a strong enhancement in near-field heat transfer. It is predicted that the heat flux between two CNT arrays can exceed that between SiC plates at any vacuum gap distance and is about 10 times higher with a 10?nm gap.

  18. Insulator for laser housing

    DOE Patents [OSTI]

    Duncan, David B. (Auburn, CA)

    1992-01-01T23:59:59.000Z

    The present invention provides a heat-resistant electrical insulator adapted for joining laser housing portions, which insulator comprises: an annulus; a channel in the annulus traversing the circumference and length of the housing; at least two ports, each communicating with the channel and an outer surface of the housing; and an attachment for securely attaching each end of the annulus to a laser housing member.

  19. Energy efficiency improvements for refrigerator/freezers using prototype doors containing gas-filled panel insulating systems

    SciTech Connect (OSTI)

    Griffith, B.; Arasteh, D.; Tuerler, D.

    1995-01-01T23:59:59.000Z

    Energy efficiency improvements in domestic refrigerator/freezers, are directly influenced by the overall thermal performance of the cabinet and doors. An advanced system for reducing heat gain is Gas-Filled Panel thermal insulation technology. Gas-Filled Panels contain a low-conductivity, inert gas at atmospheric pressure and employ a reflective baffle to suppress radiation and convection within the gas. This paper presents energy use test results for a 1993 model 500 liter top mount refrigerator/freezer operated with its original doors and with a series of alternative prototype doors. Gas-Filled Panel technology was used in two types of prototype refrigerator/freezer doors. In one design, panels were used in composite with foam in standard metal door pans; this design yielded no measurable energy savings. In the other design, special polymer door pans were fitted with panels that fill nearly all of the available insulation volume; this design yielded a 6.5% increase in energy efficiency for the entire refrigerator/freezer. The EPA Refrigerator Analysis computer program has been used to predict the change in daily energy consumption with the alternative doors. The computer model also projects a 25% energy efficiency improvement for a refrigerator/freezer that would use Gas-Filled Panel insulation throughout the cabinet as well as the doors.

  20. Infrared near-field imaging and spectroscopy based on thermal or synchrotron radiation

    SciTech Connect (OSTI)

    Peragut, Florian; De Wilde, Yannick, E-mail: yannick.dewilde@espci.fr [ESPCI ParisTech, PSL Research University, CNRS, Institut Langevin, 1 rue Jussieu, F-75005, Paris (France); Brubach, Jean-Blaise; Roy, Pascale [Société Civile Synchrotron SOLEIL, L'Orme des Merisiers, St-Aubin BP48, 91192 Gif-sur-Yvette Cedex (France)

    2014-06-23T23:59:59.000Z

    We demonstrate the coupling of a scattering near-field scanning optical microscope combined with a Fourier transform infrared spectrometer. The set-up operates using either the near-field thermal emission from the sample itself, which is proportional to the electromagnetic local density of states, or with an external infrared synchrotron source, which is broadband and highly brilliant. We perform imaging and spectroscopy measurements with sub-wavelength spatial resolution in the mid-infrared range on surfaces made of silicon carbide and gold and demonstrate the capabilities of the two configurations for super-resolved near-field mid-infrared hyperspectral imaging and that the simple use of a properly chosen bandpass filter on the detector allows one to image the spatial distribution of materials with sub-wavelength resolution by studying the contrast in the near-field images.

  1. Effective field theory calculation of nd radiative capture at thermal energies

    E-Print Network [OSTI]

    H. Sadeghi; S. Bayegan; Harald W. Griesshammer

    2006-12-03T23:59:59.000Z

    The cross section for the thermal neutron capture by the deuteron is calculated with pionless Effective Field Theory(EFT). No new Three-Nucleon forces are needed up to next-to-next-to-leading order in order to achieve cut-off independent results, besides those fixed by the triton binding energy and Nd scattering length in the triton channel. The cross-section is accurately determined to be $\\sigma_{tot}=[0.503\\pm 0.003]mb$. At zero energies, the magnetic $M1$-transition gives the dominant contribution and is calculated up to next-to-next-to-leading order (N$^2$LO). Close agreement between the available experimental data and the calculated cross section is reached. We demonstrate convergence and cutoff independence order by order in the low-energy expansion.

  2. Characterization of radiation pressure and thermal effects in a nanoscale optomechanical cavity

    E-Print Network [OSTI]

    Camacho, Ryan M; Eichenfield, Matt; Painter, Oskar

    2009-01-01T23:59:59.000Z

    Optical forces in guided-wave nanostructures have recently been proposed as an effective means of mechanically actuating and tuning optical components. In this work, we study the properties of a photonic crystal optomechanical cavity consisting of a pair of patterned silicon nitride nanobeams. Internal stresses in the stoichiometric silicon nitride thin-film are used to produce inter-beam slot-gaps ranging from 560 to 40nm. A general pump-probe measurement scheme is described which determines, self-consistently, the contributions of thermo-mechanical, thermo-optic, and radiation pressure effects. For devices with 40nm slot-gap, the optical gradient force is measured to be 134fN per cavity photon for the strongly coupled symmetric cavity supermode, producing a static cavity tuning greater than five times that of either the parasitic thermo-mechanical or thermo-optic effects.

  3. Electoral Competition, Political Uncertainty and Policy Insulation

    E-Print Network [OSTI]

    de Figueiredo, Rui J. P. Jr.

    2001-01-01T23:59:59.000Z

    Uncertainty and Policy Insulation Horn, Murray. 1995. TheUncertainty and Policy Insulation United States Congress.UNCERTAINTY AND POLICY INSULATION Rui J. P. de Figueiredo,

  4. Thermal properties of advanced aerogel insulation

    E-Print Network [OSTI]

    Cohen, Ellann

    2011-01-01T23:59:59.000Z

    Buildings consume too much energy. For example, 16.6% of all the energy used in the United States goes towards just the heating and cooling of buildings. Many governments, organizations, and companies are setting very ...

  5. THERMAL PERFORMANCE OF INSULATING WINDOW SYSTEMS

    E-Print Network [OSTI]

    Selkowitz, Stephen E.

    2011-01-01T23:59:59.000Z

    Efficient Use of Energy, New York (1975). Glaser, V.H.J. , "Energy Transport Control in Window Systems", Report ETR-1277-2, Stony Brook, New York, (

  6. THERMAL PERFORMANCE OF INSULATING WINDOW SYSTEMS

    E-Print Network [OSTI]

    Selkowitz, Stephen E.

    2011-01-01T23:59:59.000Z

    Flat Plate Solar Collectors", Solar~. 11· 151-158, (1975).atten- tion in solar collector and passive solar heatingCoeff·icients in Solar Collectors", Bulletin .Q_f the

  7. THERMAL PERFORMANCE OF INSULATING WINDOW SYSTEMS

    E-Print Network [OSTI]

    Selkowitz, Stephen E.

    2011-01-01T23:59:59.000Z

    of .16 m2·K/W (.91 hr·ft2.oF/Btu) for the combined thermalvalue of 6.25 ~;m2.K (1 .1 Btu/hr·ft ·°F) might be reduced3.4- 4.5 w;m2·K (.6- .8 Btu/hr'ft ·°F). Some techniques for

  8. Cladding Attachment Over Thick Exterior Insulating Sheathing

    SciTech Connect (OSTI)

    Baker, P.; Eng, P.; Lepage, R.

    2014-01-01T23:59:59.000Z

    The addition of insulation to the exterior of buildings is an effective means of increasing the thermal resistance of both wood framed walls as well as mass masonry wall assemblies. For thick layers of exterior insulation (levels greater than 1.5 inches), the use of wood furring strips attached through the insulation back to the structure has been used by many contractors and designers as a means to provide a convenient cladding attachment location (Straube and Smegal 2009, Pettit 2009, Joyce 2009, Ueno 2010). The research presented in this report is intended to help develop a better understanding of the system mechanics involved and the potential for environmental exposure induced movement between the furring strip and the framing. BSC sought to address the following research questions: 1. What are the relative roles of the mechanisms and the magnitudes of the force that influence the vertical displacement resistance of the system? 2. Can the capacity at a specified deflection be reliably calculated using mechanics based equations? 3. What are the impacts of environmental exposure on the vertical displacement of furring strips attached directly through insulation back to a wood structure?

  9. Interfacial Coatings for Inorganic Composite Insulation Systems

    SciTech Connect (OSTI)

    Hooker, M. W.; Fabian, P. E.; Stewart, M. W.; Grandlienard, S. D.; Kano, K. S. [Composite Technology Development, Inc., Lafayette, CO, 80026 (United States)

    2006-03-31T23:59:59.000Z

    Inorganic (ceramic) insulation materials are known to have good radiation resistance and desirable electrical and mechanical properties at cryogenic and elevated temperatures. In addition, ceramic materials can withstand the high-temperature reaction cycle used with Nb3Sn superconductor materials, allowing the insulation to be co-processed with the superconductor in a wind-and-react fabrication process. A critical aspect in the manufacture of ceramic-based insulation systems is the deposition of suitable fiber-coating materials that prevent chemical reaction of the fiber and matrix materials, and thus provide a compliant interface between the fiber and matrix, which minimizes the impact of brittle failure of the ceramic matrix. Ceramic insulation produced with CTD-FI-202 fiber interfaces have been found to exhibit very high shear and compressive strengths. However, this material is costly to produce. Thus, the goal of the present work is to evaluate alternative, lower-cost materials and processes. A variety of oxide and polyimide coatings were evaluated, and one commercially available polyimide coating has been shown to provide some improvement as compared to uncoated and de-sized S2 glass.

  10. Notes on topological insulators

    E-Print Network [OSTI]

    Dan Li; Ralph M. Kaufmann; Birgit Wehefritz-Kaufmann

    2015-01-13T23:59:59.000Z

    This paper is a survey of the $\\mathbb{Z}/\\mathbb{Z}_2$-valued invariants of topological insulators in condensed matter physics. The $\\mathbb{Z}$-valued topological invariant was originally called the TKNN invariant in physics, which has been fully understood as the first Chern number. The $\\mathbb{Z}_2$ invariant is more mysterious, we will devote our efforts to reviewing its equivalent descriptions from different point of views. We emphasize that both invariants are realizations of the Atiyah--Singer index theorem in condensed matter physics. The topological K-theory also plays an important role in the classification of topological insulators with different symmetries.

  11. Topological Mott Insulators

    SciTech Connect (OSTI)

    Raghu, S.

    2010-03-02T23:59:59.000Z

    We consider extended Hubbard models with repulsive interactions on a honeycomb lattice, and the transitions from the semimetal to Mott insulating phases at half-filling. Because of the frustrated nature of the second-neighbor interactions, topological Mott phases displaying the quantum Hall and the quantum spin Hall effects are found for spinless and spin fermion models, respectively. The mean-field phase diagram is presented and the fluctuations are treated within the random phase approximation. Renormalization group analysis shows that these states can be favored over the topologically trivial Mott insulating states.

  12. Insulation | Department of Energy

    Office of Environmental Management (EM)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742 33 111 1,613 122Commercial602 1,39732on ArmedManufacturing | Department ofInsulation Insulation

  13. The 3D thermal analysis is performed for the radiation heat load at all stages of the HRS op-

    E-Print Network [OSTI]

    McDonald, Kirk

    . The coil layers were separated from each other by two layers of insulation with a layer of Al in between and cost. The beam dump was designed to both accu- mulate the spent beam and keep its temperature and air dynamic heat loads to the cryogenic system, a reason- able lifetime of the coil components, acceptable -on

  14. Contaminant trap for gas-insulated apparatus

    DOE Patents [OSTI]

    Adcock, J.L.; Pace, M.O.; Christophorou, L.G.

    1984-01-01T23:59:59.000Z

    A resinous body is placed in gas-insulated electrical apparatus to remove particulate material from the insulating gas.

  15. A preliminary study of the linear relationship between monthly averaged daily solar radiation and daily thermal amplitude in the north of Buenos Aires provence

    E-Print Network [OSTI]

    Cionco, R; Rodriguez, R

    2012-01-01T23:59:59.000Z

    Using irradiance and temperature measurements obtained at the Facultad Regional San Nicol\\'as of UTN, we performed a preliminary study of the linear relationship between monthly averaged daily solar radiation and daily thermal amplitude. The results show a very satisfactory adjustment (R = 0.848, RMS = 0.066, RMS% = 9.690 %), even taking into account the limited number of months (36). Thus, we have a formula of predictive nature, capable of estimating mean monthly solar radiation for various applications. We expect to have new data sets to expand and improve the statistical significance of these results.

  16. Physics World Archive Topological insulators

    E-Print Network [OSTI]

    Johannesson, Henrik

    Physics World Archive Topological insulators Charles Kane, Joel Moore From Physics World February, how- ever, now uncovered a new electronic phase called a topological insulator. Putting the name; this "spin current" is a milestone in the realization of practical "spintronics". Topological insulators have

  17. Topological Insulator Nanowires and Nanoribbons

    E-Print Network [OSTI]

    Cui, Yi

    Topological Insulator Nanowires and Nanoribbons Desheng Kong, Jason C. Randel,,| Hailin Peng,, Judy material show that it is a three-dimensional topological insulator possessing conductive surface states topological insulator materials have a large surface-to-volume ratio that can manifest the conductive surface

  18. Fabrication, evaluation, and application of evacuated panel insulation (EPI) to portable coolers

    SciTech Connect (OSTI)

    Barito, R.W.; Barito, M.O. (Barito (R.W.) and Associates, Inc., Louisville, KY (USA)); Kollie, T.G.; McElroy, D.L.; Weaver, F.J.; Werst, S.H.; Chu, W.; Childs, K.W. (Oak Ridge National Lab., TN (USA)); Fine, H.A. (Kentucky Univ., Lexington, KY (USA)); Landrum, H.L. Jr. (Igloo Products Corp., Houston, TX (USA))

    1990-03-01T23:59:59.000Z

    Thermal insulation is a key parameter in the national energy equation. A reduction in energy usage was realized when chlorofluorocarbon (CFC) blown foams were utilized in thermal insulation applications; however, the discovery that CFC's are reducing the stratospheric ozone resulted in an international agreement to restrict the future production of CFC's. If viable alternatives are not developed, these restrictions will result in increased energy demands. One alternative to foams containing CFC is carbon dioxide blown foams used in a composite insulation system with evacuated panel insulation (EPI). Carbon dioxide blown foams are about 33% higher in thermal conductivity than CFC blown foams; however, EPI's are about 66% lower in conductivity than CFC blown foams. By combining these two insulations into one composite insulation system, CFC's can be eliminated and replaced by a system with lower thermal conductivity. This report covers the fabrication and evaluation of EPI's and their application in a composite panel/CFC foam insulation system in portable ice coolers. Ice coolers were used as a demonstration device because they provided a simple tool for determining the resistances of the composite insulation as compared with the foam alone. CFC foams were used as this project involved a drop-in'' replacement in a production environment where substitution of CO{sub 2} foam was not practical. 16 refs., 3 figs., 9 tabs.

  19. Identification of building applications for a variable-conductance insulation

    SciTech Connect (OSTI)

    Potter, T.F. [National Renewable Energy Lab., Golden, CO (United States); Tuluca, A. [Winter (Steven) Associates, Inc., New York, NY (United States)

    1992-07-01T23:59:59.000Z

    Recent experiments have confirmed the feasibility of controllable, reversible disabling of a vacuum insulation panel, which may result in the development of energy-efficient building envelope components. These components could extend the managed energy exchange through the building envelope from about 30% (typical with fenestration systems in commercial buildings), to as much as 90% of the gross wall and roof areas. Further investigation will be required to optimized the thermal response and the magnitude of the R-value swing (from a difference between insulating and conducting insulating values of 4 to as high as a factor of 100). The potential for energy reduction by using the variable-conductance insulation in the building envelope is discussed, and other potential building applications are mentioned.

  20. Linear particle accelerator with seal structure between electrodes and insulators

    DOE Patents [OSTI]

    Broadhurst, John H. (Golden Valley, MN)

    1989-01-01T23:59:59.000Z

    An electrostatic linear accelerator includes an electrode stack comprised of primary electrodes formed or Kovar and supported by annular glass insulators having the same thermal expansion rate as the electrodes. Each glass insulator is provided with a pair of fused-in Kovar ring inserts which are bonded to the electrodes. Each electrode is designed to define a concavo-convex particle trap so that secondary charged particles generated within the accelerated beam area cannot reach the inner surface of an insulator. Each insulator has a generated inner surface profile which is so configured that the electrical field at this surface contains no significant tangential component. A spark gap trigger assembly is provided, which energizes spark gaps protecting the electrodes affected by over voltage to prevent excessive energy dissipation in the electrode stack.

  1. Holographic fractional topological insulators

    SciTech Connect (OSTI)

    Hoyos, Carlos; Jensen, Kristan; Karch, Andreas [Department of Physics, University of Washington, Seattle, Washington 98195-1560 (United States)

    2010-10-15T23:59:59.000Z

    We give a holographic realization of the recently proposed low-energy effective action describing a fractional topological insulator. In particular we verify that the surface of this hypothetical material supports a fractional quantum Hall current corresponding to half that of a Laughlin state.

  2. Regulation of thermal conductivity in hot galaxy clusters by MHD turbulence

    E-Print Network [OSTI]

    Steven A. Balbus; Christopher S. Reynolds

    2008-06-05T23:59:59.000Z

    The role of thermal conduction in regulating the thermal behavior of cooling flows in galaxy clusters is reexamined. Recent investigations have shown that the anisotropic Coulomb heat flux caused by a magnetic field in a dilute plasma drives a dynamical instability. A long standing problem of cooling flow theory has been to understand how thermal conduction can offset radiative core losses without completely preventing them. In this Letter we propose that magnetohydrodynamic turbulence driven by the heat flux instability regulates field-line insulation and drives a reverse convective thermal flux, both of which may mediate the stabilization of the cooling cores of hot clusters. This model suggests that turbulent mixing should accompany strong thermal gradients in cooling flows. This prediction seems to be supported by the spatial distribution of metals in the central galaxies of clusters, which shows a much stronger correlation with the ambient hot gas temperature gradient than with the parent stellar population.

  3. 2D Dirac Materials: From Graphene to Topological Insulators

    E-Print Network [OSTI]

    Teweldebrhan, Desalegne Bekuretsion

    2011-01-01T23:59:59.000Z

    2D Topological Insulators. . . . . . . . . . . . . . . . .structure for a topological insulator. The Dirac cone fallsband structure for topological insulators. With the Fermi

  4. Heat insulating system for a fast reactor shield slab

    DOE Patents [OSTI]

    Kotora, J. Jr.; Groh, E.F.; Kann, W.J.; Burelbach, J.P.

    1984-04-10T23:59:59.000Z

    Improved thermal insulation for a nuclear reactor deck comprises many helical coil springs disposed in generally parallel, side-by-side laterally overlapping or interfitted relationship to one another so as to define a three-dimensional composite having both metal and voids between the metal, and enclosure means for holding the composite to the underside of the deck.

  5. A Rapid Scanning Inspection Method for Insulated Ferromagnetic Tubing

    E-Print Network [OSTI]

    Marsh, G. M.; Milewits, M.

    1984-01-01T23:59:59.000Z

    Until the present there has been no effective way to rapidly scan thermally insulated refinery or process piping for corrosion or thin wall. Such defects, if left unattended, can lead to wasteful losses of time, energy and money. To date the most...

  6. Heat transfer model of above and underground insulated piping systems

    SciTech Connect (OSTI)

    Kwon, K.C.

    1998-07-01T23:59:59.000Z

    A simplified heat transfer model of above and underground insulated piping systems was developed to perform iterative calculations for fluid temperatures along the entire pipe length. It is applicable to gas, liquid, fluid flow with no phase change. Spreadsheet computer programs of the model have been developed and used extensively to perform the above calculations for thermal resistance, heat loss and core fluid temperature.

  7. Compact vacuum insulation embodiments

    DOE Patents [OSTI]

    Benson, D.K.; Potter, T.F.

    1992-04-28T23:59:59.000Z

    An ultra-thin compact vacuum insulation panel is comprised of two hard, but bendable metal wall sheets closely spaced apart from each other and welded around the edges to enclose a vacuum chamber. Glass or ceramic spacers hold the wall sheets apart. The spacers can be discrete spherical beads or monolithic sheets of glass or ceramic webs with nodules protruding therefrom to form essentially point' or line' contacts with the metal wall sheets. In the case of monolithic spacers that form line' contacts, two such spacers with the line contacts running perpendicular to each other form effectively point' contacts at the intersections. Corrugations accommodate bending and expansion, tubular insulated pipes and conduits, and preferred applications are also included. 26 figs.

  8. Compact vacuum insulation

    DOE Patents [OSTI]

    Benson, David K. (Golden, CO); Potter, Thomas F. (Denver, CO)

    1993-01-01T23:59:59.000Z

    An ultra-thin compact vacuum insulation panel is comprised of two hard, but bendable metal wall sheets closely spaced apart from each other and welded around the edges to enclose a vacuum chamber. Glass or ceramic spacers hold the wall sheets apart. The spacers can be discrete spherical beads or monolithic sheets of glass or ceramic webs with nodules protruding therefrom to form essentially "point" or "line" contacts with the metal wall sheets. In the case of monolithic spacers that form "line" contacts, two such spacers with the line contacts running perpendicular to each other form effectively "point" contacts at the intersections. Corrugations accommodate bending and expansion, tubular insulated pipes and conduits, and preferred applications are also included.

  9. Compact vacuum insulation

    DOE Patents [OSTI]

    Benson, D.K.; Potter, T.F.

    1993-01-05T23:59:59.000Z

    An ultra-thin compact vacuum insulation panel is comprised of two hard, but bendable metal wall sheets closely spaced apart from each other and welded around the edges to enclose a vacuum chamber. Glass or ceramic spacers hold the wall sheets apart. The spacers can be discrete spherical beads or monolithic sheets of glass or ceramic webs with nodules protruding therefrom to form essentially point'' or line'' contacts with the metal wall sheets. In the case of monolithic spacers that form line'' contacts, two such spacers with the line contacts running perpendicular to each other form effectively point'' contacts at the intersections. Corrugations accommodate bending and expansion, tubular insulated pipes and conduits, and preferred applications are also included.

  10. Compact vacuum insulation embodiments

    DOE Patents [OSTI]

    Benson, David K. (Golden, CO); Potter, Thomas F. (Denver, CO)

    1992-01-01T23:59:59.000Z

    An ultra-thin compact vacuum insulation panel is comprised of two hard, but bendable metal wall sheets closely spaced apart from each other and welded around the edges to enclose a vacuum chamber. Glass or ceramic spacers hold the wall sheets apart. The spacers can be discrete spherical beads or monolithic sheets of glass or ceramic webs with nodules protruding therefrom to form essentially "point" or "line" contacts with the metal wall sheets. In the case of monolithic spacers that form "line" contacts, two such spacers with the line contacts running perpendicular to each other form effectively "point" contacts at the intersections. Corrugations accommodate bending and expansion, tubular insulated pipes and conduits, and preferred applications are also included.

  11. Use of roof temperature modeling to predict necessary conditions for locating wet insulation with infrared thermography

    SciTech Connect (OSTI)

    Childs, K.W.

    1985-11-01T23:59:59.000Z

    In low-sloped roofing systems using porous insulation, the presence of water can significantly degrade thermal performance. For this reason, it is desirable to develop a reliable method for detecting the presence of water in a roofing system. Because of the different thermal characteristics of wet and dry insulation, there is often a surface temperature differential between areas containing wet insulation and areas containing dry insulation. Under the right circumstances, the areas of wet insulation can be detected by means of infrared sensing techniques. These techniques have already gained widespread acceptance, but there is still some uncertainty as to what are appropriate environmental conditions for viewing. To better define the conditions under which infrared techniques can distinguish between areas of wet and dry insulation, a one-dimensional, transient heat transfer model of a roofing system was developed. The model considers conduction through the roof, insolation on the surface, radiant exchange between the roof and sky, convective heat transfer between the roof and air, and the influence of trapped moisture on the thermal properties of the insulation. A study was undertaken using this model to develop an easily-applied technique for prediction of necessary conditions for locating wet roof insulation using infrared thermography.

  12. Ceramic electrical insulation for electrical coils, transformers, and magnets

    DOE Patents [OSTI]

    Rice, John A. (Longmont, CO); Hazelton, Craig S. (Lafayette, CO); Fabian, Paul E. (Broomfield, CO)

    2002-01-01T23:59:59.000Z

    A high temperature electrical insulation is described, which is suitable for electrical windings for any number of applications. The inventive insulation comprises a cured preceramic polymer resin, which is preferably a polysiloxane resin. A method for insulating electrical windings, which are intended for use in high temperature environments, such as superconductors and the like, advantageously comprises the steps of, first, applying a preceramic polymer layer to a conductor core, to function as an insulation layer, and second, curing the preceramic polymer layer. The conductor core preferably comprises a metallic wire, which may be wound into a coil. In the preferred method, the applying step comprises a step of wrapping the conductor core with a sleeve or tape of glass or ceramic fabric which has been impregnated by a preceramic polymer resin. The inventive insulation system allows conducting coils and magnets to be fabricated using existing processing equipment, and maximizes the mechanical and thermal performance at both elevated and cryogenic temperatures. It also permits co-processing of the wire and the insulation to increase production efficiencies and reduce overall costs, while still remarkably enhancing performance.

  13. External Insulation of Masonry Walls and Wood Framed Walls

    SciTech Connect (OSTI)

    Baker, P.

    2013-01-01T23:59:59.000Z

    The use of exterior insulation on a building is an accepted and effective means to increase the overall thermal resistance of the assembly that also has other advantages of improved water management and often increased air tightness of building assemblies. For thin layers of insulation (1" to 1 1/2"), the cladding can typically be attached directly through the insulation back to the structure. For thicker insulation layers, furring strips have been added as a cladding attachment location. This approach has been used in the past on numerous Building America test homes and communities (both new and retrofit applications), and has been proven to be an effective and durable means to provide cladding attachment. However, the lack of engineering data has been a problem for many designers, contractors, and code officials. This research project developed baseline engineering analysis to support the installation of thick layers of exterior insulation on existing masonry and frame walls. Furthermore, water management details necessary to integrate windows, doors, decks, balconies and roofs were created to provide guidance on the integration of exterior insulation strategies with other enclosure elements.

  14. Hydrogen in semiconductors and insulators

    E-Print Network [OSTI]

    Van de Walle, Chris G.

    2007-01-01T23:59:59.000Z

    level in two different semiconductors, illustrating the06-01999R1 Hydrogen in semiconductors and insulators SpecialA. oxide materials; A. semiconductors; C. electronic

  15. Composition and process for making an insulating refractory material

    SciTech Connect (OSTI)

    Pearson, Alan (Murrysville, PA); Swansiger, Thomas G. (Apollo, PA)

    1998-04-28T23:59:59.000Z

    A composition and process for making an insulating refractory material. The composition includes calcined alumina powder, flash activated alumina powder, an organic polymeric binder and a liquid vehicle which is preferably water. Starch or modified starch may also be added. A preferred insulating refractory material made with the composition has a density of about 2.4-2.6 g/cm.sup.3 with reduced thermal conductivity, compared with tabular alumina. Of importance, the formulation has good abrasion resistance and crush strength during intermediate processing (commercial sintering) to attain full strength and refractoriness, good abrasion resistance and crush strength.

  16. Cladding Attachment Over Thick Exterior Insulating Sheathing (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2013-11-01T23:59:59.000Z

    The addition of insulation to the exterior of buildings is an effective means of increasing the thermal resistance of wood-framed walls and mass masonry wall assemblies. The location of the insulation on the exterior of the structure has many direct benefits, including better effective R-value from reduced thermal bridging, better condensation resistance, reduced thermal stress on the structure, as well as other commonly associated improvements such as increased airtightness and improved water management. For thick layers of exterior insulation (more than 1.5 in.), the use of wood furring strips attached through the insulation back to the structure has been used by many contractors and designers as a means to provide a convenient cladding attachment location. Although the approach has proven effective, there is significant resistance to its widespread implementation due to a lack of research and understanding of the mechanisms involved in the development of the vertical displacement resistance capacity. In addition, the long-term in-service performance of the system has been questioned due to potential creep effects of the assembly under the sustained dead load of the cladding and effects of varying environmental conditions. In addition, the current International Building Code (IBC) and International Residential Code (IRC) do not have a provision that specifically allows this assembly.

  17. Preradiation studies for non-thermal Z-pinch wire load experiments on Saturn

    SciTech Connect (OSTI)

    Sanford, T.W.L.; Humphreys, D.R.; Poukey, J.W.; Marder, B.M.; Halbleib, J.A.; Crow, J.T.; Spielman, R.B. [Sandia National Labs., Albuquerque, NM (United States); Mock, R.C. [Ktech Corp., Albuquerque, NM (United States)

    1994-06-01T23:59:59.000Z

    The implosion dynamics of compact wire arrays on Saturn are explored as a function of wire mass m, wire length {ell}, wire radii R, and radial power-flow feed geometry using the ZORK code. Electron losses and the likelihood of arcing in the radial feed adjacent the wire load are analyzed using the TWOQUICK and CYLTRAN codes. The physical characteristics of the implosion and subsequent thermal radiation production are estimated using the LASNEX code in one dimension. These analyses show that compact tungsten wire arrays with parameters suggested by D. Mosher and with a 21-nH vacuum feed geometry satisfy the empirical scaling criterion I/(M/{ell}) {approximately} 2 MA/(mg/cm) of Mosher for optimizing non-thermal radiation from z pinches, generate low electron losses in the radial feeds, and generate electric fields at the insulator stack below the Charlie Martin flashover limit thereby permitting full power to be delivered to the load. Under such conditions, peak currents of {approximately}5 MA can be delivered to wire loads {approximately}20 ns before the driving voltage reverses at the insulator stack, potentially allowing the m = 0 instability to develop with the subsequent emission of non-thermal radiation as predicted by the Mosher model.

  18. Radiation Characteristics of Glass Containing Gas Bubbles

    E-Print Network [OSTI]

    Pilon, Laurent; Viskanta, Raymond

    2003-01-01T23:59:59.000Z

    B. L. Drolen, “Thermal radiation in particulate media withRadiation Characteristics of Glass Containing Gas Bubblesthermophysical properties and radiation characteristics of

  19. Insulation | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742EnergyOnItemResearch > The Energy Materials Center at CornellOf NSECAtomInsulation

  20. Insulation | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page onYouTube YouTube Note: Since the.pdfBreaking of BlytheDepartment ofEnergy1EnergyEnergy InsulateandInsulation

  1. Superconducting ``metals'' and ``insulators'' Smitha Vishveshwara

    E-Print Network [OSTI]

    Superconducting ``metals'' and ``insulators'' Smitha Vishveshwara Department of Physics, University to the distinction between normal metals and insulators: the superconducting ``metal'' with delocalized qua- siparticle excitations and the superconducting ``insulator'' with localized quasiparticles. We describe

  2. Variably insulating portable heater/cooler

    DOE Patents [OSTI]

    Potter, Thomas F. (Denver, CO)

    1998-01-01T23:59:59.000Z

    A compact vacuum insulation panel comprising a chamber enclosed by two sheets of metal, glass-like spaces disposed in the chamber between the sidewalls, and a high-grade vacuum in the chamber includes apparatus and methods for enabling and disabling, or turning "on" and "off" the thermal insulating capability of the panel. One type of enabling and disabling apparatus and method includes a metal hydride for releasing hydrogen gas into the chamber in response to heat, and a hydrogen grate between the metal hydride and the chamber for selectively preventing and allowing return of the hydrogen gas to the metal hydride. Another type of enabling and disabling apparatus and method includes a variable emissivity coating on the sheets of metal in which the emissivity is controllably variable by heat or electricity. Still another type of enabling and disabling apparatus and method includes metal-to-metal contact devices that can be actuated to establish or break metal-to-metal heat paths or thermal short circuits between the metal sidewalls.

  3. Material-controlled dynamic vacuum insulation

    DOE Patents [OSTI]

    Benson, David K. (14154 W. First Dr., Golden, CO 80401); Potter, Thomas F. (515 S. Magnolia La., Denver, CO 80224)

    1996-10-08T23:59:59.000Z

    A compact vacuum insulation panel comprising a chamber enclosed by two sheets of metal, glass-like spaces disposed in the chamber between the sidewalls, and a high-grade vacuum in the chamber includes apparatus and methods for enabling and disabling, or turning "on" and "off" the thermal insulating capability of the panel. One type of enabling and disabling apparatus and method includes a metal hydride for releasing hydrogen gas into the chamber in response to heat, and a hydrogen grate between the metal hydride and the chamber for selectively preventing and allowing return of the hydrogen gas to the metal hydride. Another type of enabling and disabling apparatus and method includes a variable emissivity coating on the sheets of metal in which the emissivity is controllably variable by heat or electricity. Still another type of enabling and disabling apparatus and method includes metal-to-metal contact devices that can be actuated to establish or break metal-to-metal heat paths or thermal short circuits between the metal sidewalls.

  4. Variably insulating portable heater/cooler

    DOE Patents [OSTI]

    Potter, T.F.

    1998-09-29T23:59:59.000Z

    A compact vacuum insulation panel is described comprising a chamber enclosed by two sheets of metal, glass-like spaces disposed in the chamber between the sidewalls, and a high-grade vacuum in the chamber includes apparatus and methods for enabling and disabling, or turning ``on`` and ``off`` the thermal insulating capability of the panel. One type of enabling and disabling apparatus and method includes a metal hydride for releasing hydrogen gas into the chamber in response to heat, and a hydrogen grate between the metal hydride and the chamber for selectively preventing and allowing return of the hydrogen gas to the metal hydride. Another type of enabling and disabling apparatus and method includes a variable emissivity coating on the sheets of metal in which the emissivity is controllably variable by heat or electricity. Still another type of enabling and disabling apparatus and method includes metal-to-metal contact devices that can be actuated to establish or break metal-to-metal heat paths or thermal short circuits between the metal sidewalls. 25 figs.

  5. Material-controlled dynamic vacuum insulation

    DOE Patents [OSTI]

    Benson, D.K.; Potter, T.F.

    1996-10-08T23:59:59.000Z

    A compact vacuum insulation panel is described comprising a chamber enclosed by two sheets of metal, glass-like spaces disposed in the chamber between the sidewalls, and a high-grade vacuum in the chamber includes apparatus and methods for enabling and disabling, or turning ``on`` and ``off`` the thermal insulating capability of the panel. One type of enabling and disabling apparatus and method includes a metal hydride for releasing hydrogen gas into the chamber in response to heat, and a hydrogen grate between the metal hydride and the chamber for selectively preventing and allowing return of the hydrogen gas to the metal hydride. Another type of enabling and disabling apparatus and method includes a variable emissivity coating on the sheets of metal in which the emissivity is controllably variable by heat or electricity. Still another type of enabling and disabling apparatus and method includes metal-to-metal contact devices that can be actuated to establish or break metal-to-metal heat paths or thermal short circuits between the metal sidewalls. 25 figs.

  6. Aerogel Impregnated Polyurethane Piping and Duct Insulation ...

    Energy Savers [EERE]

    Aerogel Impregnated Polyurethane Piping and Duct Insulation Aerogel Impregnated Polyurethane Piping and Duct Insulation Emerging Technologies Project for the 2013 Building...

  7. Flipping Photoelectron Spins in Topological Insulators

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

    Flipping Photoelectron Spins in Topological Insulators Flipping Photoelectron Spins in Topological Insulators Print Tuesday, 23 April 2013 10:00 Inherently strange crystalline...

  8. Flipping Photoelectron Spins in Topological Insulators

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

    Flipping Photoelectron Spins in Topological Insulators Print Inherently strange crystalline materials called 3D topological insulators (TIs) are all the rage in materials science....

  9. HYDROPHOBIC CHARACTERISTICS OF COMPOSITE INSULATORS IN SIMULATED INLAND ARID DESERT ENVIRONMENT

    SciTech Connect (OSTI)

    Khan, Yasin; Al-Arainy, Abdulrehman Ali; Malik, Nazar Hussain; Qureshi, Muhammad Iqbal [Department of Electrical Engineering, College of Engineering, King Saud University, Riyadh 11421 (Saudi Arabia)

    2010-06-15T23:59:59.000Z

    Presently along with traditional insulators i.e. glass and porcelain, etc., the polymeric insulators are also used world widely. These polymeric insulators are very sensitive to various environmental parameters e.g. UV radiations, heat, etc. The UV radiation level in the central region of Saudi Arabia is high as compared to the recommended IEC-61109 standard for the accelerated aging of the composite insulators. In this study, thermoplastic elastomer (TPE) and Ethylene Propylene Diene Monomer (EPDM) insulators were subjected to accelerated aging stress as per IEC standard as well as modified IEC standard simulating the inland arid desert's atmospheric conditions. The hydrophobic characteristics were studied by measuring the contact angle along the insulator surface before and after the accelerated aging of the samples. It was found that TPE loses its hydrophobic properties more as compared to EPDM insulator. This loss was proportional to the intensity of UV irradiation. The rate of recovery is also low for both the tested materials as compared to Silicone Rubber insulators.

  10. SiGe-free strained Si on insulator by wafer bonding and layer transfer T. A. Langdo,a)

    E-Print Network [OSTI]

    SiGe-free strained Si on insulator by wafer bonding and layer transfer T. A. Langdo,a) M. T. Currie; accepted 4 April 2003 SiGe-free strained Si on insulator substrates were fabricated by wafer bonding even after SiGe layer removal. The strain in the structure is thermally stable during 1000 °C anneals

  11. Advanced insulations for refrigerator/freezers: The potential for new shell designs incorporating polymer barrier construction

    SciTech Connect (OSTI)

    Griffith, B.T.; Arasteh, D.

    1992-11-01T23:59:59.000Z

    The impending phase-out of chlorofluorocarbons (CFCs) used to expand foam insulation, combined with requirements for increased energy efficiency, make the use of non-CFC-based high performance insulation technologies increasingly attractive. The majority of current efforts are directed at using advanced insulations in the form of thin, flat low-conductivity gas-filled or evacuated orthogonal panels, which we refer to as Advanced Insulation Panels (AIPs). AIPs can be used in composite with blown polymer foams to improve insulation performance in refrigerator/freezers (R/Fs) of conventional design and manufacture. This AIP/foam composite approach is appealing because it appears to be a feasible, near-term method for incorporating advanced insulations into R/Fs without substantial redesign or retooling. However, the requirements for adequate flow of foam during the foam-in-place operation impose limitations on the allowable thickness and coverage area of AIPs. This report examines design alternatives which may offer a greater increase in overall thermal resistance than is possible with the use of AIP/foam composites in current R/F design. These design alternatives generally involve a basic redesign of the R/F taking into account the unique requirements of advanced insulations and the importance of minimizing thermal bridging with high thermal resistance insulations. The focus here is on R/F doors because they are relatively simple and independent R/F components and are therefore good candidates for development of alterative designs. R/F doors have significant thermal bridging problems due to the steel outer shell construction. A three dimensional finite difference computer modeling exercise of a R/F door geometry was used to compare the overall levels of thermal resistance (R-value) for various design configurations.

  12. Evaluation of the Thermal Performance for a Wire Mesh/Hollow Glass Microsphere Composite Structure as a Conduction Barrier

    E-Print Network [OSTI]

    Mckenna, Sean

    2010-01-15T23:59:59.000Z

    An experimental investigation exploring the use of wire mesh/hollow glass microsphere combination for use as thermal insulation was conducted with the aim to conclude whether or not it represents a superior insulation technology to those...

  13. Multiple layer insulation cover

    DOE Patents [OSTI]

    Farrell, James J. (Livingston Manor, NY); Donohoe, Anthony J. (Ovid, NY)

    1981-11-03T23:59:59.000Z

    A multiple layer insulation cover for preventing heat loss in, for example, a greenhouse, is disclosed. The cover is comprised of spaced layers of thin foil covered fabric separated from each other by air spaces. The spacing is accomplished by the inflation of spaced air bladders which are integrally formed in the cover and to which the layers of the cover are secured. The bladders are inflated after the cover has been deployed in its intended use to separate the layers of the foil material. The sizes of the material layers are selected to compensate for sagging across the width of the cover so that the desired spacing is uniformly maintained when the cover has been deployed. The bladders are deflated as the cover is stored thereby expediting the storage process and reducing the amount of storage space required.

  14. Multidimensional thermal structure of magnetized neutron star envelopes

    E-Print Network [OSTI]

    Jeremy S. Heyl; Lars Hernquist

    1998-08-12T23:59:59.000Z

    Recently launched x-ray telescopes have discovered several candidate isolated neutron stars. The thermal radiation from these objects may potentially constrain our understanding of nuclear physics in a realm inaccessible to terrestrial experiments. To translate the observed fluxes from neutron stars into constraints, one needs precise calculations of the heat transfer through the thin insulating envelopes of neutron stars. We describe models of the thermal structure of the envelopes of neutron stars with magnetic fields up to 10^{14} G. Unlike earlier work, we infer the properties of envelope models in two dimensions and precisely account for the quantization of the electron phase space. Both dipole and uniformly magnetized envelopes are considered.

  15. Chromatin insulators: lessons from the fly

    E-Print Network [OSTI]

    Corces, Victor G.

    Chromatin insulators: lessons from the fly B.V.Gurudatta and Victor G.Corces Abstract Chromatin insulators are DNA^protein complexes with broad functions in nuclear biology. Drosophila has at least five different types of insulators; recent results suggest that these different insulators share some components

  16. Solar Decathlon Technology Spotlight: Structural Insulated Panels

    Broader source: Energy.gov [DOE]

    Structural insulated panels (SIPs) are prefabricated structural elements used to build walls, ceilings, floors, and roofs.

  17. Tunable Dirac Fermion Dynamics in Topological Insulators

    E-Print Network [OSTI]

    Wang, Wei Hua

    Tunable Dirac Fermion Dynamics in Topological Insulators Chaoyu Chen1 , Zhuojin Xie1 , Ya Feng1, Beijing 100190, China. Three-dimensional topological insulators are characterized by insulating bulk state topological insulators. We have directly revealed signatures of the electron-phonon coupling and found

  18. Catalytic thermal barrier coatings

    DOE Patents [OSTI]

    Kulkarni, Anand A. (Orlando, FL); Campbell, Christian X. (Orlando, FL); Subramanian, Ramesh (Oviedo, FL)

    2009-06-02T23:59:59.000Z

    A catalyst element (30) for high temperature applications such as a gas turbine engine. The catalyst element includes a metal substrate such as a tube (32) having a layer of ceramic thermal barrier coating material (34) disposed on the substrate for thermally insulating the metal substrate from a high temperature fuel/air mixture. The ceramic thermal barrier coating material is formed of a crystal structure populated with base elements but with selected sites of the crystal structure being populated by substitute ions selected to allow the ceramic thermal barrier coating material to catalytically react the fuel-air mixture at a higher rate than would the base compound without the ionic substitutions. Precious metal crystallites may be disposed within the crystal structure to allow the ceramic thermal barrier coating material to catalytically react the fuel-air mixture at a lower light-off temperature than would the ceramic thermal barrier coating material without the precious metal crystallites.

  19. PHYSICAL REVIEW B 85, 155422 (2012) Near-field thermal radiation transfer controlled by plasmons in graphene

    E-Print Network [OSTI]

    Soljaèiæ, Marin

    2012-01-01T23:59:59.000Z

    in graphene Ognjen Ilic,1,* Marinko Jablan,2 John D. Joannopoulos,1 Ivan Celanovic,3 Hrvoje Buljan,2 and Marin-field radiation transfer between two closely separated graphene sheets. The dependence of near-field heat exchange interband or intraband processes. We predict maximum transfer at low doping and for plasmons in two graphene

  20. Correlation effects on topological insulator

    E-Print Network [OSTI]

    Xiong-Jun Liu; Yang Liu; Xin Liu

    2010-11-24T23:59:59.000Z

    The strong correlation effects on topological insulator are studied in a two-sublattice system with an onsite single-particle energy difference $\\Delta$ between two sublattices. At $\\Delta=0$, increasing the onsite interaction strength $U$ drives the transition from the quantum spin Hall insulating state to the non-topological antiferromagnetic Mott-insulating (AFMI) state. When $\\Delta$ is larger than a certain value, a topologically trivial band insulator or AFMI at small values of $U$ may change into a quantum anomalous Hall state with antiferromagnetic ordering at intermediate values of $U$. Further increasing $U$ drives the system back into the topologically trivial state of AFMI. The corresponding phenomena is observable in the solid state and cold atom systems. We also propose a scheme to realize and detect these effects in cold atom systems.

  1. Measure Guideline: Basement Insulation Basics

    SciTech Connect (OSTI)

    Aldrich, R.; Mantha, P.; Puttagunta, S.

    2012-10-01T23:59:59.000Z

    This guideline is intended to describe good practices for insulating basements in new and existing homes, and is intended to be a practical resources for building contractors, designers, and also to homeowners.

  2. Suppression of static electrification of insulating oil for large power transformers

    SciTech Connect (OSTI)

    Yasuda, M.; Goto, K.; Ishii, T.; Masunaga, M.; Mori, E.; Okubo, H.

    1982-11-01T23:59:59.000Z

    Streaming electrification of large power transformers is discussed here from the standpoint of characteristics of insulating oils used in them. First, the relation between the thermal degradation and charging tendency of insulating oils is defined to show that suppressing the degradation of oils to be caused by long term operation of the transformers can minimize the rise in charging tendency, leading to suppressed streaming electrification within the transformer. Second, experimental results show that alkylbenzene mixture oil and benzotriazol additive oil are excellent in charging characteristics when used as insulating oils of large power transformers.

  3. Fully synthetic taped insulation cables

    DOE Patents [OSTI]

    Forsyth, Eric B. (Brookhaven, NY); Muller, Albert C. (Center Moriches, NY)

    1984-01-01T23:59:59.000Z

    A high voltage oil-impregnated electrical cable with fully polymer taped insulation operable to 765 kV. Biaxially oriented, specially processed, polyethylene, polybutene or polypropylene tape with an embossed pattern is wound in multiple layers over a conductive core with a permeable screen around the insulation. Conventional oil which closely matches the dielectric constant of the tape is used, and the cable can be impregnated after field installation because of its excellent impregnation characteristics.

  4. Non-thermal Plasma Chemistry Non-thermal Thermal

    E-Print Network [OSTI]

    Greifswald, Ernst-Moritz-Arndt-Universität

    -thermal Plasma Chemical Flow Reactor #12;Werner von Siemens ,, ... construction of an apparatus generation (1857) pollution control volatile organic components, NOx reforming, ... radiation sources excimer;Leuchtstoffröhre Plasma-Bildschirm Energiesparlampe #12;electrical engineering light sources textile industry

  5. GROUND PLANE INSULATION FAILURE IN THE FIRST TPC SUPERCONDUCTING COIL

    E-Print Network [OSTI]

    Green, M.A.

    2010-01-01T23:59:59.000Z

    is WIUUTEO GROUND PLANE INSULATION FAILURE IN THE FIRST TPCOn August 27, 1980, an insulation failure occurred dt-ringby a failure uf ground plane insulation. ACKNOWLEDGMENTS The

  6. Microsecond switchable thermal antenna

    SciTech Connect (OSTI)

    Ben-Abdallah, Philippe, E-mail: pba@institutoptique.fr; Benisty, Henri; Besbes, Mondher [Laboratoire Charles Fabry, UMR 8501, Institut d'Optique, CNRS, Université Paris-Sud 11, 2, Avenue Augustin Fresnel, 91127 Palaiseau Cedex (France)

    2014-07-21T23:59:59.000Z

    We propose a thermal antenna that can be actively switched on and off at the microsecond scale by means of a phase transition of a metal-insulator material, the vanadium dioxide (VO{sub 2}). This thermal source is made of a periodically patterned tunable VO{sub 2} nanolayer, which support a surface phonon-polariton in the infrared range in their crystalline phase. Using electrodes properly registered with respect to the pattern, the VO{sub 2} phase transition can be locally triggered by ohmic heating so that the surface phonon-polariton can be diffracted by the induced grating, producing a highly directional thermal emission. Conversely, when heating less, the VO{sub 2} layers cool down below the transition temperature, the surface phonon-polariton cannot be diffracted anymore so that thermal emission is inhibited. This switchable antenna could find broad applications in the domain of active thermal coatings or in those of infrared spectroscopy and sensing.

  7. Process for making ceramic insulation

    DOE Patents [OSTI]

    Akash, Akash (Salt Lake City, UT); Balakrishnan, G. Nair (Sandy, UT)

    2009-12-08T23:59:59.000Z

    A method is provided for producing insulation materials and insulation for high temperature applications using novel castable and powder-based ceramics. The ceramic components produced using the proposed process offers (i) a fine porosity (from nano-to micro scale); (ii) a superior strength-to-weight ratio; and (iii) flexibility in designing multilayered features offering multifunctionality which will increase the service lifetime of insulation and refractory components used in the solid oxide fuel cell, direct carbon fuel cell, furnace, metal melting, glass, chemical, paper/pulp, automobile, industrial heating, coal, and power generation industries. Further, the ceramic components made using this method may have net-shape and/or net-size advantages with minimum post machining requirements.

  8. A review of vacuum insulation research and development in the Building Materials Group of the Oak Ridge National Laboratory

    SciTech Connect (OSTI)

    Kollie, T.G.; McElroy, D.L.; Fine, H.A.; Childs, K.W.; Graves, R.S.; Weaver, F.J.

    1991-09-01T23:59:59.000Z

    This report is a summary of the development work on flat-vacuum insulation performed by the Building Materials Group (BMG) in the Metals and Ceramics Division of the Oak Ridge National Laboratory (ORNL) during the last two years. A historical review of the technology of vacuum insulation is presented, and the role that ORNL played in this development is documented. The ORNL work in vacuum insulation has been concentrated in Powder-filled Evacuated Panels (PEPs) that have a thermal resistivity over 2.5 times that of insulating foams and seven times that of many batt-type insulations, such as fiberglass. Experimental results of substituting PEPs for chlorofluorocarbon (CFC) foal insulation in Igloo Corporation ice coolers are summarized. This work demonstrated that one-dimensional (1D) heat flow models overestimated the increase in thermal insulation of a foam/PEP-composite insulation, but three-dimensional (3D) models provided by a finite-difference, heat-transfer code (HEATING-7) accurately predicted the resistance of the composites. Edges and corners of the ice coolers were shown to cause the errors in the 1D models as well as shunting of the heat through the foam and around the PEPs. The area of coverage of a PEP in a foam/PEP composite is established as an important parameter in maximizing the resistance of such composites. 50 refs., 27 figs,. 22 tabs.

  9. Enhanced thermal and gas flow performance in a three-way catalytic...

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

    thermal and gas flow performance in a three-way catalytic converter through use of insulation within the ceramic monolith Enhanced thermal and gas flow performance in a three-way...

  10. Approximating Metal-Insulator Transitions

    E-Print Network [OSTI]

    C. Danieli; K. Rayanov; B. Pavlov; G. Martin; S. Flach

    2014-05-06T23:59:59.000Z

    We consider quantum wave propagation in one-dimensional quasiperiodic lattices. We propose an iterative construction of quasiperiodic potentials from sequences of potentials with increasing spatial period. At each finite iteration step the eigenstates reflect the properties of the limiting quasiperiodic potential properties up to a controlled maximum system size. We then observe approximate metal-insulator transitions (MIT) at the finite iteration steps. We also report evidence on mobility edges which are at variance to the celebrated Aubry-Andre model. The dynamics near the MIT shows a critical slowing down of the ballistic group velocity in the metallic phase similar to the divergence of the localization length in the insulating phase.

  11. Insulation board and process of making

    DOE Patents [OSTI]

    Nowobilski, Jeffert J. (Orchard Park, NY); Owens, William J. (Kenmore, NY)

    1985-01-01T23:59:59.000Z

    Insulation board capable of bearing a load without significant loss of insulating capacity due to compression, produced by a method wherein the board is made in compliance with specified conditions of time, temperature and pressure.

  12. Insulator damage endangers public, power reliability; ratepayers...

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

    for tips about multiple incidents of insulators damaged by firearms on its high-voltage power line near Joint Base Lewis-McChord in Tacoma, Wash. Damaged insulators can put...

  13. Effects of Framing on the Thermal Performance of Wood and Steel-Framed Walls

    E-Print Network [OSTI]

    Kosny, J.; Yarbrough, D. W.; Childs, P.; Mohiuddin, S. A.

    2006-01-01T23:59:59.000Z

    , the consequences of installation imperfections in cavity insulation on thermal performance are analyzed. The results of the study demonstrated significant sensitivity in some configurations of residential walls to the framing factor and insulation installation... imperfections. Keywords R-value, Framing Factor, Cavity Insulation, Framing Effect Coefficient, Steel Frame walls, Wood-frame walls TERMINOLOGY OF THE WHOLE WALL R-VALUE PROCEDURE USED IN THIS PAPER The following list of thermal performance...

  14. High Reliability R-10 Windows Using Vacuum Insulating Glass Units

    SciTech Connect (OSTI)

    Stark, David

    2012-08-16T23:59:59.000Z

    The objective of this effort was for EverSealed Windows (“EverSealed” or “ESW”) to design, assemble, thermally and environmentally test and demonstrate a Vacuum Insulating Glass Unit (“VIGU” or “VIG”) that would enable a whole window to meet or exceed the an R-10 insulating value (U-factor ? 0.1). To produce a VIGU that could withstand any North American environment, ESW believed it needed to design, produce and use a flexible edge seal system. This is because a rigid edge seal, used by all other know VIG producers and developers, limits the size and/or thermal environment of the VIG to where the unit is not practical for typical IG sizes and cannot withstand severe outdoor environments. The rigid-sealed VIG’s use would be limited to mild climates where it would not have a reasonable economic payback when compared to traditional double-pane or triple-pane IGs. ESW’s goals, in addition to achieving a sufficiently high R-value to enable a whole window to achieve R-10, included creating a VIG design that could be produced for a cost equal to or lower than a traditional triple-pane IG (low-e, argon filled). ESW achieved these goals. EverSealed produced, tested and demonstrated a flexible edge-seal VIG that had an R-13 insulating value and the edge-seal system durability to operate reliably for at least 40 years in the harshest climates of North America.

  15. "Pushing the boundaries in state-of-the-art thermal management

    E-Print Network [OSTI]

    Acton, Scott

    and capabilities include: thin film aerogel coating for thermal and electrical insulation in MEMS and MMIC devices materials or interstitial layers; · Isolation of heat affected regions with thermal insulation--aerogels is primarily supported by the internationally renowned Nanoscale Heat Transfer and Aerogel Research

  16. New fabrication method of silicon field emitter arrays using thermal oxidation

    E-Print Network [OSTI]

    Lee, Jong Duk

    Vacuum Society. I. INTRODUCTION For most applications of vacuum microelectronics such as flat panel array using pure thermal oxide as a gate insulator are described. Since the thermally grown oxide film has a better stoichiometry and is a better insulator than the evaporated oxide, the fabrication

  17. Dynamics of Dirac Fermions in Topological Insulators

    E-Print Network [OSTI]

    Arnold, Anton

    Dynamics of Dirac Fermions in Topological Insulators R. Hammer1 , C. Ertler1 , W. P¨otz1 , and A.hammer@uni-graz.at Abstract We study the coherent dynamics of Dirac fermions on the surface of topological insulators in one topological insulators (TI) we investigate theoretically the dynamics of Dirac fermion wave packets on their 2

  18. A Holographic Fractional Topological Insulator

    E-Print Network [OSTI]

    Carlos Hoyos-Badajoz; Kristan Jensen; Andreas Karch

    2010-07-19T23:59:59.000Z

    We give a holographic realization of the recently proposed low energy effective action describing a fractional topological insulator. In particular we verify that the surface of this hypothetical material supports a fractional quantum Hall current corresponding to half that of a Laughlin state.

  19. Unsteady heat dissipation in accelerator superconducting coils insulated with porous ceramic insulation in normal and supercritical helium conditions

    SciTech Connect (OSTI)

    Pietrowicz, S. [Department of Thermodynamics, Institute of Power Engineering and Fluid Mechanics, Wroc?aw University of Technology, Wybrze?e Wyspia?skiego 27, 50 - 370 Wroc?aw (Poland); Four, A.; Baudouy, B. [CEA Saclay, Irfu/ SACM, 91191 Gif-sur-Yvette (France); Kimura, N.; Yamamoto, A. [High Energy Accelerator Research Organization, KEK, Tsukuba, Ibaraki 305-0801 (Japan)

    2014-01-29T23:59:59.000Z

    To investigate the unsteady heat dissipation in accelerator superconducting coils insulated with porous ceramic insulation, two experimental mock-ups reproducing the thermal and the mechanical conditions of a superconducting coils were produced. The mock-ups with compressive load of 10 MPa and 20 MPa were tested at normal (T = 4.23 K and p = 1 bar) and supercritical helium conditions (T = 4.23 K and p = 2.0 to 3.75 bar) during unsteady heat dissipation. The paper presents the experimental results of temperature rise in both superconducting coils as a function of time for a wide range of a localized heat load varying from 0.1 kJ/m{sup 3} up to 12.8 MJ m{sup ?3} per pulse. A numerical model of the transient process in these coils has been developed and the computations are compared with the experimental results.

  20. advanced thermal interface: Topics by E-print Network

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

    Danny Grant; Gabriel Robles-de-la-Torre 2004-01-01 210 Thermal properties of advanced aerogel insulation MIT - DSpace Summary: Buildings consume too much energy. For example,...

  1. advanced thermally stable: Topics by E-print Network

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

    19 20 21 22 23 24 25 Next Page Last Page Topic Index 121 Thermal properties of advanced aerogel insulation MIT - DSpace Summary: Buildings consume too much energy. For example,...

  2. advanced thermal control: Topics by E-print Network

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

    100 MeV. Noriyoshi Ishii; Hideo Suganuma 2003-12-27 273 Thermal properties of advanced aerogel insulation MIT - DSpace Summary: Buildings consume too much energy. For example,...

  3. advanced thermal processing: Topics by E-print Network

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

    19 20 21 22 23 24 25 Next Page Last Page Topic Index 301 Thermal properties of advanced aerogel insulation MIT - DSpace Summary: Buildings consume too much energy. For example,...

  4. Making Steel Framing as Thermally Efficient as Wood 

    E-Print Network [OSTI]

    Kosny, J.; Childs, P.

    2002-01-01T23:59:59.000Z

    the steel web with a less conductive material, and 4) placing foam insulation in locations where the thermal shorts are most critical. Researchers at Oak Ridge National Laboratory (ORNL) have utilized both hot box testing and computer simulations in aim...

  5. A Comparative Heat Transfer Examination of Structural Insulated Panels (SIPs) With and Without Phase Change Materials (PCMs) Using a Dynamic Wall Simulator

    E-Print Network [OSTI]

    Medina, M.; Zhu, D.

    The main focus of this paper was to present data to advance the design of a previously developed thermally-enhanced structural insulated panel (SIP) that had been outfitted with phase change materials (PCMs) (Medina et al., 2008). To advance...

  6. Thermal Analysis of Novel Underfill Materials with Optimum Processing Characteristics

    E-Print Network [OSTI]

    Harmon, Julie P.

    - date the morphology of these composites. © 2005 Wiley Peri- odicals, Inc. J Appl Polym Sci 98: 1300 chip. Polymers are thermally insulating mate- rials; the thermal conductivity of a typical polymer the compos- ite thermal conductivity up to 32.5 W/m K at the maximum filler loading of 78 vol %. Polymer

  7. DIAGNOSIS OF INSULATED BUILDING WALLS USING PASSIVE INFRARED THERMOGRAPHY AND NUMERICAL SIMULATIONS

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    DIAGNOSIS OF INSULATED BUILDING WALLS USING PASSIVE INFRARED THERMOGRAPHY AND NUMERICAL SIMULATIONS This work presents the thermal monitoring of a multi-layered wall of a restored building (PANISSE platform parameters. Then they are compared with thermocouple measurements and numerical simulations. KEYWORDS

  8. Window Spacers and Edge Seals in Insulating Glass Units: A State-of-the-Art

    E-Print Network [OSTI]

    carbon dioxide (CO2) emissions in buildings is by increasing the thermal performance of their envelopes. Gustavsen Norwegian University of Science and Technology Windows and Envelope Materials Group Building), Windows & Envelope Materials Group, Berkeley, CA 94720- 8134, USA Abstract Insulating glass (IG) units

  9. Microwave-induced spin currents in ferromagnetic-insulator|normal-metal bilayer system

    SciTech Connect (OSTI)

    Agrawal, Milan, E-mail: magrawal@physik.uni-kl.de [Fachbereich Physik and Landesforschungszentrum OPTIMAS, Technische Universität Kaiserslautern, 67663 Kaiserslautern (Germany); Graduate School Materials Science in Mainz, Gottlieb-Daimler-Strasse 47, 67663 Kaiserslautern (Germany); Serga, Alexander A.; Lauer, Viktor; Papaioannou, Evangelos Th.; Hillebrands, Burkard; Vasyuchka, Vitaliy I. [Fachbereich Physik and Landesforschungszentrum OPTIMAS, Technische Universität Kaiserslautern, 67663 Kaiserslautern (Germany)

    2014-09-01T23:59:59.000Z

    A microwave technique is employed to simultaneously examine the spin pumping and the spin Seebeck effect processes in a YIG|Pt bilayer system. The experimental results show that for these two processes, the spin current flows in opposite directions. The temporal dynamics of the longitudinal spin Seebeck effect exhibits that the effect depends on the diffusion of bulk thermal-magnons in the thermal gradient in the ferromagnetic-insulator|normal-metal system.

  10. Insulation assembly for electric machine

    SciTech Connect (OSTI)

    Rhoads, Frederick W.; Titmuss, David F.; Parish, Harold; Campbell, John D.

    2013-10-15T23:59:59.000Z

    An insulation assembly is provided that includes a generally annularly-shaped main body and at least two spaced-apart fingers extending radially inwards from the main body. The spaced-apart fingers define a gap between the fingers. A slot liner may be inserted within the gap. The main body may include a plurality of circumferentially distributed segments. Each one of the plurality of segments may be operatively connected to another of the plurality of segments to form the continuous main body. The slot liner may be formed as a single extruded piece defining a plurality of cavities. A plurality of conductors (extendable from the stator assembly) may be axially inserted within a respective one of the plurality of cavities. The insulation assembly electrically isolates the conductors in the electric motor from the stator stack and from other conductors.

  11. Magnetically insulated transmission line oscillator

    DOE Patents [OSTI]

    Bacon, Larry D. (Albuquerque, NM); Ballard, William P. (Albuquerque, NM); Clark, M. Collins (Albuquerque, NM); Marder, Barry M. (Albuquerque, NM)

    1988-01-01T23:59:59.000Z

    A magnetically insulated transmission line oscillator employs self-generated magnetic fields to generate microwave energy. An anode of the oscillator includes slow-wave structures which are formed of a plurality of thin conductive vanes defining cavities therebetween, and a gap is formed between the anode and a cathode of the oscillator. In response to a pulsed voltage applied to the anode and cathode, self-generated magnetic fields arfe produced in a cross-field orientation with respect to the orientation of the electric field between the anode and the cathode. The cross-field magnetic fields insulate the flow of electrons in the gap and confine the flow of electrons within the gap.

  12. Topological Insulators at Room Temperature

    SciTech Connect (OSTI)

    Zhang, Haijun; /Beijing, Inst. Phys.; Liu, Chao-Xing; /Tsinghua U., Beijing; Qi, Xiao-Liang; /Stanford U., Phys. Dept.; Dai, Xi; Fang, Zhong; /Beijing, Inst. Phys.; Zhang, Shou-Cheng; /Stanford U., Phys. Dept.

    2010-03-25T23:59:59.000Z

    Topological insulators are new states of quantum matter with surface states protected by the time-reversal symmetry. In this work, we perform first-principle electronic structure calculations for Sb{sub 2}Te{sub 3}, Sb{sub 2}Se{sub 3}, Bi{sub 2}Te{sub 3} and Bi{sub 2}Se{sub 3} crystals. Our calculations predict that Sb{sub 2}Te{sub 3}, Bi{sub 2}T e{sub 3} and Bi{sub 2}Se{sub 3} are topological insulators, while Sb{sub 2}Se{sub 3} is not. In particular, Bi{sub 2}Se{sub 3} has a topologically non-trivial energy gap of 0.3eV , suitable for room temperature applications. We present a simple and unified continuum model which captures the salient topological features of this class of materials. These topological insulators have robust surface states consisting of a single Dirac cone at the {Lambda} point.

  13. Method for forming fibrous silicon carbide insulating material

    DOE Patents [OSTI]

    Wei, G.C.

    1983-10-12T23:59:59.000Z

    A method whereby silicon carbide-bonded SiC fiber composites are prepared from carbon-bonded C fiber composites is disclosed. Carbon-bonded C fiber composite material is treated with gaseous silicon monoxide generated from the reaction of a mixture of colloidal silica and carbon black at an elevated temperature in an argon atmosphere. The carbon in the carbon bond and fiber is thus chemically converted to SiC resulting in a silicon carbide-bonded SiC fiber composite that can be used for fabricating dense, high-strength high-toughness SiC composites or as thermal insulating materials in oxidizing environments.

  14. Method for forming fibrous silicon carbide insulating material

    DOE Patents [OSTI]

    Wei, George C. (Oak Ridge, TN)

    1984-01-01T23:59:59.000Z

    A method whereby silicon carbide-bonded SiC fiber composites are prepared from carbon-bonded C fiber composites is disclosed. Carbon-bonded C fiber composite material is treated with gaseous silicon monoxide generated from the reaction of a mixture of colloidal silica and carbon black at an elevated temperature in an argon atmosphere. The carbon in the carbon bond and fiber is thus chemically converted to SiC resulting in a silicon carbide-bonded SiC fiber composite that can be used for fabricating dense, high-strength high-toughness SiC composites or as thermal insulating materials in oxidizing environments.

  15. DETERMINING THE OPTIMUM PLACEMENT OF A PHASE CHANGE MATERIALS (PCM) THERMAL SHIELD INSIDE FRAME WALLS USING A DYNAMIC WALL SIMULATOR

    E-Print Network [OSTI]

    Reshmeen, Silvia

    2009-12-23T23:59:59.000Z

    ABSTRACT This thesis presents the results of an experimental study to determine the optimum placement and the thermal performance of a Phase Change Materials (PCMs) thermal shield incorporated into frame wall insulation systems for the purpose...

  16. Recycling of wasted energy : thermal to electrical energy conversion

    E-Print Network [OSTI]

    Lim, Hyuck

    2011-01-01T23:59:59.000Z

    solar radiation, and the geothermal energy. [16] Fig. 1.1.thermal energy, geothermal energy, wasted heat from athermal energy, geothermal energy, ocean thermal energy,

  17. Recycling of wasted energy : thermal to electrical energy conversion

    E-Print Network [OSTI]

    Lim, Hyuck

    2011-01-01T23:59:59.000Z

    biological thermal energy, geothermal energy, wasted heatpower plants, solar thermal energy, geothermal energy, oceansolar radiation, and the geothermal energy. [16] Fig. 1.1.

  18. Floating insulated conductors for heating subsurface formations

    DOE Patents [OSTI]

    Burns, David; Goodwin, Charles R.

    2014-07-29T23:59:59.000Z

    A heating system for a subsurface formation includes a conduit located in a first opening in the subsurface formation. Three electrical conductors are located in the conduit. A return conductor is located inside the conduit. The return conductor is electrically coupled to the ends of the electrical conductors distal from the surface of the formation. Insulation is located inside the conduit. The insulation electrically insulates the three electrical conductors, the return conductor, and the conduit from each other.

  19. T-Duality of Topological Insulators

    E-Print Network [OSTI]

    Varghese Mathai; Guo Chuan Thiang

    2015-04-08T23:59:59.000Z

    Topological insulators and D-brane charges in string theory can both be classified by the same family of groups. In this letter, we extend this connection via a geometric transform, giving a novel duality of topological insulators which can be viewed as a condensed matter analog of T-duality in string theory. For 2D Chern insulators, this duality exchanges the rank and Chern number of the valence bands.

  20. Building America Expert Meeting: Interior Insulation Retrofit...

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

    Building Science Corporation team held an Expert Meeting on Interior Insulation Retrofit of Mass Masonry Wall Assemblies on July 30, 2011, at the Westford Regency Hotel in...

  1. Farmers RECC- Residential Insulation Rebate Program

    Broader source: Energy.gov [DOE]

    The Farmers Rural Electric Cooperative (RECC) Button-Up Program provides free energy audits and rebates for insulation upgrades to its residential customers. Farmers RECC's energy advisor will...

  2. How Much Insulation is Too Much?

    Broader source: Energy.gov [DOE]

    This presentation was given at the Summer 2012 DOE Building America meeting on July 25, 2012, and addressed the question "How much insulation is too much?"

  3. Studies Bolster Promise of Topological Insulators

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

    Studies Bolster Promise of Topological Insulators Print A few years ago, a strange new material began to drive research in condensed-matter physics around the world. First...

  4. Issue 5: Optimizing High Levels of Insulation

    Broader source: Energy.gov [DOE]

    This presentation was given at the Summer 2012 DOE Building America meeting on July 25, 2012, and addressed the question "How much insulation is too much?"

  5. Upgrade of the LHC magnet interconnections thermal shielding

    SciTech Connect (OSTI)

    Musso, Andrea; Barlow, Graeme; Bastard, Alain; Charrondiere, Maryline; Deferne, Guy; Dib, Gaëlle; Duret, Max; Guinchard, Michael; Prin, Hervé; Craen, Arnaud Vande; Villiger, Gilles [CERN European Organization for Nuclear Research, Meyrin 1211, Geneva 23, CH (Switzerland); Chrul, Anna [The Henryk Niewodniczanski Institute of Nuclear Physics, Polish Academy of Sciences, ul.Radzikowskiego 152, 31-324 Krakow (Poland); Damianoglou, Dimitrios [NTUA National Technical University of Athens, Heeron Polytechniou 9, 15780 Zografou (Greece); Strychalski, Micha? [Wroclaw University of Technology, Faculty of Mechanical and Power Engineering, Wyb. Wyspianskiego 27, Wroclaw, 50-370 (Poland); Wright, Loren [Lancaster University, Bailrigg, Lancaster, LA1 4YW (United Kingdom)

    2014-01-29T23:59:59.000Z

    The about 1700 interconnections (ICs) between the Large Hadron Collider (LHC) superconducting magnets include thermal shielding at 50-75 K, providing continuity to the thermal shielding of the magnet cryostats to reduce the overall radiation heat loads to the 1.9 K helium bath of the magnets. The IC shield, made of aluminum, is conduction-cooled via a welded bridge to the thermal shield of the adjacent magnets which is actively cooled. TIG welding of these bridges made in the LHC tunnel at installation of the magnets induced a considerable risk of fire hazard due to the proximity of the multi-layer insulation of the magnet shields. A fire incident occurred in one of the machine sectors during machine installation, but fortunately with limited consequences thanks to prompt intervention of the operators. LHC is now undergoing a 2 years technical stop during which all magnet's ICs will have to be opened to consolidate the magnet electrical connections. The IC thermal shields will therefore have to be removed and re-installed after the work is completed. In order to eliminate the risk of fire hazard when re-welding, it has been decided to review the design of the IC shields, by replacing the welded bridges with a mechanical clamping which also preserves its thermal function. An additional advantage of this new solution is the ease in dismantling for maintenance, and eliminating weld-grinding operations at removal needing radioprotection measures because of material activation after long-term operation of the LHC. This paper describes the new design of the IC shields and in particular the theoretical and experimental validation of its thermal performance. Furthermore a status report of the on-going upgrade work in the LHC is given.

  6. Economics of PPP-insulated pipe-type cable: Final report

    SciTech Connect (OSTI)

    Ernst, A.

    1987-10-01T23:59:59.000Z

    This study has been designed to establish the economic range of application and the potential cost advantage of PPP-insulated pipe-type cable compared with presently utilized paper-insulated designs. The study is in two parts. In the first part the electrical and thermal characteristics of a range of cable sizes are tabulated. This data can be utilized for planning and economic comparison purposes. In the second part 12 transmission load scenarios are studied to determine the relative cost of various designs considering materials, installation and the losses over a wide range of assumptions.

  7. On Holographic Insulators and Supersolids

    E-Print Network [OSTI]

    Kiritsis, Elias

    2015-01-01T23:59:59.000Z

    We obtain holographic realisations for systems that have strong similarities to Mott insulators and supersolids, after examining the ground states of Einstein-Maxwell-scalar systems. The real part of the AC conductivity has a hard gap and a discrete spectrum only. We add momentum dissipation to resolve the delta function in the conductivity due to translational invariance. We develop tools to directly calculate the Drude weight for a large class of solutions and to support our claims. Numerical RG flows are also constructed to verify that such saddle points are IR fixed points of asymptotically AdS_4 geometries.

  8. Fully synthetic taped insulation cables

    DOE Patents [OSTI]

    Forsyth, E.B.; Muller, A.C.

    1983-07-15T23:59:59.000Z

    The present invention is a cable which, although constructed from inexpensive polyolefin tapes and using typical impregnating oils, furnishes high voltage capability up to 765 kV, and has such excellent dielectric characteristics and heat transfer properties that it is capable of operation at capacities equal to or higher than presently available cables at a given voltage. This is accomplished by using polyethylene, polybutene or polypropylene insulating tape which has been specially processed to attain properties which are not generally found in these materials, but are required for their use in impregnated electrical cables. Chief among these properties is compatibility with impregnating oil.

  9. Insulation Materials | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page onYouTube YouTube Note: Since the.pdfBreaking of BlytheDepartment ofEnergy1EnergyEnergy Insulate

  10. NREL Evaluates the Thermal Performance of Uninsulated Walls to Improve the Accuracy of Building Energy Simulation Tools (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2012-01-01T23:59:59.000Z

    This technical highlight describes NREL research to develop models of uninsulated wall assemblies that help to improve the accuracy of building energy simulation tools when modeling potential energy savings in older homes. Researchers at the National Renewable Energy Laboratory (NREL) have developed models for evaluating the thermal performance of walls in existing homes that will improve the accuracy of building energy simulation tools when predicting potential energy savings of existing homes. Uninsulated walls are typical in older homes where the wall cavities were not insulated during construction or where the insulating material has settled. Accurate calculation of heat transfer through building enclosures will help determine the benefit of energy efficiency upgrades in order to reduce energy consumption in older American homes. NREL performed detailed computational fluid dynamics (CFD) analysis to quantify the energy loss/gain through the walls and to visualize different airflow regimes within the uninsulated cavities. The effects of ambient outdoor temperature, radiative properties of building materials, and insulation level were investigated. The study showed that multi-dimensional airflows occur in walls with uninsulated cavities and that the thermal resistance is a function of the outdoor temperature - an effect not accounted for in existing building energy simulation tools. The study quantified the difference between CFD prediction and the approach currently used in building energy simulation tools over a wide range of conditions. For example, researchers found that CFD predicted lower heating loads and slightly higher cooling loads. Implementation of CFD results into building energy simulation tools such as DOE2 and EnergyPlus will likely reduce the predicted heating load of homes. Researchers also determined that a small air gap in a partially insulated cavity can lead to a significant reduction in thermal resistance. For instance, a 4-in. tall air gap (Figure 1a) led to a 15% reduction in resistance. Similarly, a 2-ft tall air gap (Figure 1c) led to 54% reduction in thermal resistance. NREL researchers plan to extend this study to include additional wall configurations, and also to evaluate the performance of attic spaces with different insulation levels. NREL's objective is to address each potential issue that leads to inaccuracies in building energy simulation tools to improve the predictions.

  11. Modular cell biology: retroactivity and insulation Domitilla Del Vecchio1,

    E-Print Network [OSTI]

    Sontag, Eduardo

    Modular cell biology: retroactivity and insulation Domitilla Del Vecchio1, *, Alexander J Ninfa2 a remarkable insulation property, due to the fast timescales of the phosphorylation and dephosphorylation: computational methods; metabolic and regulatory networks Keywords: feedback; insulation; modularity; singular

  12. Low-cost exterior insulation process and structure

    DOE Patents [OSTI]

    Vohra, Arun (Bethesda, MD)

    1999-01-01T23:59:59.000Z

    A low-cost exterior insulation process of stacking bags of insulating material against a wall and covering them with wire mesh and stucco provides a durable structure with good insulating value.

  13. Topological insulators of bosons/spins T. Senthil (MIT)

    E-Print Network [OSTI]

    Topological insulators of bosons/spins T. Senthil (MIT) Thanks: X.-G.Wen, M.P.A. Fisher Trivial phases Eg: Band insulators, superfluids, antiferromagnets, ......... Gapped `topologically ordered phases Eg: Band insulators, superfluids, antiferromagnets, ......... Gapped `topologically ordered

  14. Classification and characterization of topological insulators and superconductors

    E-Print Network [OSTI]

    Mong, Roger

    2012-01-01T23:59:59.000Z

    Antiferromagnetic topological insulators 5.1 Z 2 topological1.3 Topological insulators in 3D . . . . . . . . . . . . .1.3.1 Strong topological insulators (STI) . . . . . 1.3.2

  15. Widespread spin polarizationeffects in photoemission from topological insulators

    E-Print Network [OSTI]

    Jozwiak, C.

    2012-01-01T23:59:59.000Z

    photoemission from topological insulators C. Jozwiak, 1, ?approach in the 3D topological insulators. [1] D. Hsieh, D.three-dimensional topological insulator Bi 2 Se 3 using a

  16. Low-cost exterior insulation process and structure

    DOE Patents [OSTI]

    Vohra, A.

    1999-03-02T23:59:59.000Z

    A low-cost exterior insulation process of stacking bags of insulating material against a wall and covering them with wire mesh and stucco provides a durable structure with good insulating value. 2 figs.

  17. Insulating Structural Ceramics Program, Final Report

    SciTech Connect (OSTI)

    Andrews, Mark J.; Tandon, Raj; Ott, Eric; Hind, Abi Akar; Long, Mike; Jensen, Robert; Wheat, Leonard; Cusac, Dave; Lin, H. T.; Wereszczak, Andrew A.; Ferber, Mattison K.; Lee, Sun Kun; Yoon, Hyung K.; Moreti, James; Park, Paul; Rockwood, Jill; Boyer, Carrie; Ragle, Christie; Balmer-Millar, Marilou; Aardahl, Chris; Habeger, Craig; Rappe, Ken; Tran, Diana; Koshkarian, Kent; Readey, Michael; ,

    2005-11-22T23:59:59.000Z

    New materials and corresponding manufacturing processes are likely candidates for diesel engine components as society and customers demand lower emission engines without sacrificing power and fuel efficiency. Strategies for improving thermal efficiency directly compete with methodologies for reducing emissions, and so the technical challenge becomes an optimization of controlling parameters to achieve both goals. Approaches being considered to increase overall thermal efficiency are to insulate certain diesel engine components in the combustion chamber, thereby increasing the brake mean effective pressure ratings (BMEP). Achieving higher BMEP rating by insulating the combustion chamber, in turn, requires advances in material technologies for engine components such as pistons, port liners, valves, and cylinder heads. A series of characterization tests were performed to establish the material properties of ceramic powder. Mechanical chacterizations were also obtained from the selected materials as a function of temperature utilizing ASTM standards: fast fracture strength, fatique resistance, corrosion resistance, thermal shock, and fracture toughness. All ceramic materials examined showed excellent wear properties and resistance to the corrosive diesel engine environments. The study concluded that the ceramics examined did not meet all of the cylinder head insert structural design requirements. Therefore we do not recommend at this time their use for this application. The potential for increased stresses and temperatures in the hot section of the diesel engine combined with the highly corrosive combustion products and residues has driven the need for expanded materials capability for hot section engine components. Corrosion and strength requirements necessitate the examination of more advanced high temperture alloys. Alloy developments and the understanding of processing, structure, and properties of supperalloy materials have been driven, in large part, by the gas turbine community over the last fifty years. Characterization of these high temperature materials has, consequently, concentrated heavily upon application conditions similiar to to that encountered in the turbine engine environment. Significantly less work has been performed on hot corrosion degradation of these materials in a diesel engine environment. This report examines both the current high temperature alloy capability and examines the capability of advanced nickle-based alloys and methods to improve production costs. Microstructures, mechanical properties, and the oxidation/corrosion behavior of commercially available silicon nitride ceramics were investigated for diesel engine valve train applications. Contact, sliding, and scratch damage mechanisms of commercially available silicon nitride ceramics were investigated as a function of microstructure. The silicon nitrides with a course microstructure showed a higher material removal rate that agrees with a higher wear volume in the sliding contact tests. The overall objective of this program is to develop catalyst materials systems for an advanced Lean-NOx aftertreatment system that will provide high NOx reduction with minimum engine fuel efficiency penalty. With Government regulations on diesel engine NOx emissions increasingly becoming more restrictive, engine manufacturers are finding it difficult to meet the regulations solely with engine design strategies (i.e. improved combustion, retarded timing, exhaust gas recirculation, etc.). Aftertreatment is the logical technical approach that will be necessary to achieve the required emission levels while at the same time minimally impacting the engine design and its associated reliability and durability concerns.

  18. Thermally switchable dielectrics

    DOE Patents [OSTI]

    Dirk, Shawn M.; Johnson, Ross S.

    2013-04-30T23:59:59.000Z

    Precursor polymers to conjugated polymers, such as poly(phenylene vinylene), poly(poly(thiophene vinylene), poly(aniline vinylene), and poly(pyrrole vinylene), can be used as thermally switchable capacitor dielectrics that fail at a specific temperature due to the non-conjugated precursor polymer irreversibly switching from an insulator to the conjugated polymer, which serves as a bleed resistor. The precursor polymer is a good dielectric until it reaches a specific temperature determined by the stability of the leaving groups. Conjugation of the polymer backbone at high temperature effectively disables the capacitor, providing a `built-in` safety mechanism for electronic devices.

  19. THERMAL CONDUCTIVITY OF POWDER INSULATIONS FOR CRYOGENIC STORAGE

    E-Print Network [OSTI]

    Chang, Ho-Myung

    aerogel over the temperature range 10 K to 275 K. hi this research, a guarded parallel plate experimental

  20. Charge and spin topological insulators

    SciTech Connect (OSTI)

    Kopaev, Yu. V., E-mail: kopaev@sci.lebedev.ru; Gorbatsevich, A. A.; Belyavskii, V. I. [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation)

    2011-09-15T23:59:59.000Z

    The topologically nontrivial states of matter-charge and spin topological insulators, which exhibit, respectively, properties of the integer quantum Hall effect and the quantum spin Hall effect-are discussed. The topological characteristics (invariant with respect to weak adiabatic changes in the Hamiltonian parameters) which lead to such states are considered. The model of a 2D hexagonal lattice having symmetries broken with respect to time reversal and spatial inversion which was proposed by Haldane and marked the beginning of unprecedented activity in the study of topologically nontrivial states is discussed. This model relates the microscopic nature of the symmetry breaking with respect to the time reversal to the occurrence of spontaneous orbital currents which circulate within a unit cell. Such currents become zero upon summation over the unit cell, but they may form spreading current states at the surface which are similar to the edge current states under the quantum Hall effect. The first model of spontaneous currents (exciton insulator model) is considered, and the possibility of implementing new topologically nontrivial states in this model is discussed.

  1. Uniform insulation applied-B ion diode

    DOE Patents [OSTI]

    Seidel, David B. (Albuquerque, NM); Slutz, Stephen A. (Albuquerque, NM)

    1988-01-01T23:59:59.000Z

    An applied-B field extraction ion diode has uniform insulation over an anode surface for increased efficiency. When the uniform insulation is accomplished with anode coils, and a charge-exchange foil is properly placed, the ions may be focused at a point on the z axis.

  2. Kingspan Insulated Panels: Order (2013-CE-5353)

    Broader source: Energy.gov [DOE]

    DOE ordered Kingspan Insulated Panels, Inc. to pay a $8,000 civil penalty after finding Kingspan Insulated Panels had failed to certify that any basic models of walk-in cooler and freezer components comply with the applicable energy conservation standards.

  3. Surprising Control over Photoelectrons from a Topological Insulator

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

    Surprising Control over Photoelectrons from a Topological Insulator Surprising Control over Photoelectrons from a Topological Insulator Print Tuesday, 12 March 2013 00:00...

  4. Graphene physics and insulator-metal transition in compressed...

    Office of Scientific and Technical Information (OSTI)

    Graphene physics and insulator-metal transition in compressed hydrogen Citation Details Title: Graphene physics and insulator-metal transition in compressed hydrogen Authors:...

  5. Materials - Next-generation insulation ... | ornl.gov

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

    Materials - Next-generation insulation ... A composite foam insulation panel being developed by Oak Ridge National Laboratory and partners could reduce wall-generated heating and...

  6. Exterior Rigid Insulation Best Practices - Building America Top...

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

    Exterior Rigid Insulation Best Practices - Building America Top Innovation Exterior Rigid Insulation Best Practices - Building America Top Innovation Effec guid-exterior rigid...

  7. Building America Expert Meeting Report: Interior Insulation Retrofit...

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

    Interior Insulation Retrofit of Mass Masonry Wall Assembliesessment of risk factors for premature building deterioration due to interior insulation retrofits, and methods to reduce...

  8. Sensitivity of forced air distribution system efficiency to climate, duct location, air leakage and insulation

    E-Print Network [OSTI]

    Walker, Iain

    2001-01-01T23:59:59.000Z

    Location, Air Leakage and Insulation Iain S. Walker Energy4 Duct Insulation, Location and Leakageinsulation

  9. ITER Central Solenoid Coil Insulation Qualification

    SciTech Connect (OSTI)

    Martovetsky, Nicolai N [ORNL] [ORNL; Mann Jr, Thomas Latta [ORNL] [ORNL; Miller, John L [ORNL] [ORNL; Freudenberg, Kevin D [ORNL] [ORNL; Reed, Richard P [Cryogenic Materials, Inc.] [Cryogenic Materials, Inc.; Walsh, Robert P [Florida State University] [Florida State University; McColskey, J D [National Institute of Standards and Technology (NIST), Boulder] [National Institute of Standards and Technology (NIST), Boulder; Evans, D [Advanced Cryogenic Materials] [Advanced Cryogenic Materials

    2010-01-01T23:59:59.000Z

    An insulation system for ITER Central Solenoid must have sufficiently high electrical and structural strength. Design efforts to bring stresses in the turn and layer insulation within allowables failed. It turned out to be impossible to eliminate high local tensile stresses in the winding pack. When high local stresses can not be designed out, the qualification procedure requires verification of the acceptable structural and electrical strength by testing. We built two 4x4 arrays of the conductor jacket with two options of the CS insulation and subjected the arrays to 1.2 million compressive cycles at 60 MPa and at 76 K. Such conditions simulated stresses in the CS insulation. We performed voltage withstand tests and after end of cycling we measured the breakdown voltages between in the arrays. After that we dissectioned the arrays and studied micro cracks in the insulation. We report details of the specimens preparation, test procedures and test results.

  10. ITER CENTRAL SOLENOID COIL INSULATION QUALIFICATION

    SciTech Connect (OSTI)

    Martovetsky, N N; Mann, T L; Miller, J R; Freudenberg, K D; Reed, R P; Walsh, R P; McColskey, J D; Evans, D

    2009-06-11T23:59:59.000Z

    An insulation system for ITER Central Solenoid must have sufficiently high electrical and structural strength. Design efforts to bring stresses in the turn and layer insulation within allowables failed. It turned out to be impossible to eliminate high local tensile stresses in the winding pack. When high local stresses can not be designed out, the qualification procedure requires verification of the acceptable structural and electrical strength by testing. We built two 4 x 4 arrays of the conductor jacket with two options of the CS insulation and subjected the arrays to 1.2 million compressive cycles at 60 MPa and at 76 K. Such conditions simulated stresses in the CS insulation. We performed voltage withstand tests and after end of cycling we measured the breakdown voltages between in the arrays. After that we dissectioned the arrays and studied micro cracks in the insulation. We report details of the specimens preparation, test procedures and test results.

  11. Intrinsic ultrathin topological insulators grown via molecular beam epitaxy characterized by in-situ angle resolved photoemission spectroscopy

    SciTech Connect (OSTI)

    Lee, J. J.; Vishik, I. M.; Ma, Y.; Shen, Z. X. [Department of Applied Physics, Stanford University, Stanford, California 94305 (United States); Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025 (United States); Geballe Laboratory for Advanced Materials, Department of Applied Physics, Stanford University, Stanford, California 94305 (United States); Schmitt, F. T.; Moore, R. G. [Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025 (United States); Geballe Laboratory for Advanced Materials, Department of Applied Physics, Stanford University, Stanford, California 94305 (United States)

    2012-07-02T23:59:59.000Z

    We demonstrate the capability of growing high quality ultrathin (10 or fewer quintuple layers) films of the topological insulators Bi{sub 2}Se{sub 3} and Bi{sub 2}Te{sub 3} using molecular beam epitaxy. Unlike previous growth techniques, which often pin the Fermi energy in the conduction band for ultrathin samples, our samples remain intrinsic bulk insulators. We characterize these films using in-situ angle resolved photoemission spectroscopy, which is a direct probe of bandstructure, and ex-situ atomic force microscopy. We find that the conduction band lies above the Fermi energy, indicating bulk insulating behavior with only the surface states crossing the Fermi energy. The use of a thermal cracker allows for more stoichiometric flux rates during growth, while still creating intrinsically doped films, paving the way for future improvements in growth of topological insulators.

  12. Rheological behavior and cryogenic properties of cyanate ester/epoxy insulation material for fusion superconducting magnet

    SciTech Connect (OSTI)

    Wu, Z. X.; Huang, C. J. [Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, PR (China); Li, L. F. [Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, PR China and State Key Laboratory of Technologies in Space Cryogenic Propellants, Technical Institute of Physics and Chemistry, C (China); Li, J. W. [Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, PR China and University of Chinese Academy of Sciences, Beijing 100049, PR (China); Tan, R.; Tu, Y. P. [North China Electric Power University, Beijing 102206, PR (China)

    2014-01-27T23:59:59.000Z

    In a Tokamak fusion reactor device like ITER, insulation materials for superconducting magnets are usually fabricated by a vacuum pressure impregnation (VPI) process. Thus these insulation materials must exhibit low viscosity, long working life as well as good radiation resistance. Previous studies have indicated that cyanate ester (CE) blended with epoxy has an excellent resistance against neutron irradiation which is expected to be a candidate insulation material for a fusion magnet. In this work, the rheological behavior of a CE/epoxy (CE/EP) blend containing 40% CE was investigated with non-isothermal and isothermal viscosity experiments. Furthermore, the cryogenic mechanical and electrical properties of the composite were evaluated in terms of interlaminar shear strength and electrical breakdown strength. The results showed that CE/epoxy blend had a very low viscosity and an exceptionally long processing life of about 4 days at 60 °C.

  13. A round robin evaluation of the corrosiveness of wet residential insulation by electrochemical measurements

    SciTech Connect (OSTI)

    Stansbury, E.E. (Stansbury (E.E.), Knoxville, TN (United States))

    1991-10-01T23:59:59.000Z

    The results of a round cabin evaluation of the use of an electrochemical method of calculating the corrosion rate of low carbon steel in environments related to cellulosic building insulations are reported. Environments included the leachate from a wet cellulosic insulation and solutions based on pure and commercial grades of borax, ammonium sulfate and aluminum sulfate. The pH values of these environments were in the range of 2.5 to 9.5. Electrochemical measurements were made using a direct reading corrosion rate instrument. The calculated corrosion rates were compared with those determined directly by weight loss measurements. Electrochemical measurements were made over a period of 48 hours and weight loss exposures were for two weeks. Poor agreement was observed for the corrosion rates determined electrochemically and the values were consistently larger than those based on weight loss. Reasons proposed for these results included the complex nature of the corrosion product deposits and the control these deposits have on oxygen diffusion to the metal interface. Both factors influence the validity of the calculation of the corrosion rate by the direct reading instrument. It was concluded that development of a viable electrochemical method of general applicability to the evaluation of the corrosiveness of wet residential building thermal insulations were doubtful. Because of the controlling influence of dissolved oxygen on the corrosion rate in the insulation leachate, an alternate evaluation method is proposed in which a thin steel specimen is partially immersed in wet insulation for three weeks. The corrosiveness of the wet insulation is evaluated in terms of the severity of attack near the metal-air-wet insulation interface. With thin metal specimens, complete penetration along the interface is proposed as a pass/fail criterion. An environment of sterile cotton wet with distilled water is proposed as a comparative standard. 9 refs., 2 figs., 3 tabs.

  14. Automatic insulation resistance testing apparatus

    DOE Patents [OSTI]

    Wyant, Francis J.; Nowlen, Steven P.; Luker, Spencer M.

    2005-06-14T23:59:59.000Z

    An apparatus and method for automatic measurement of insulation resistances of a multi-conductor cable. In one embodiment of the invention, the apparatus comprises a power supply source, an input measuring means, an output measuring means, a plurality of input relay controlled contacts, a plurality of output relay controlled contacts, a relay controller and a computer. In another embodiment of the invention the apparatus comprises a power supply source, an input measuring means, an output measuring means, an input switching unit, an output switching unit and a control unit/data logger. Embodiments of the apparatus of the invention may also incorporate cable fire testing means. The apparatus and methods of the present invention use either voltage or current for input and output measured variables.

  15. A study of changes in foundation insulation levels in the United States

    SciTech Connect (OSTI)

    Christian, J.E. (Oak Ridge National Lab., TN (United States)); Voss, M.K. (Saint Mary's Coll., Winona, MN (United States))

    1992-10-01T23:59:59.000Z

    For almost 10 years the US Department of Energy (DOE) has sponsored a small research effort with. the objective of working with the building industry to see that cost-effective foundation insulation levels are installed in all US buildings. One of the first discoveries in 1983--1984 was that less than 5% of the existing buildings had foundation insulation and less than 30% of new construction included foundation insulation. After producing foundation handbooks, actively working with energy code and standards groups (ASHRAE and Council of American Building Officials: Model Energy Code Committee) conducting told experiments, and developing computer models for predicting energy savings has any measurable progress been made toward the fulfillment of this DOE objective Also, in order to derive maximum energy savings impact for this ongoing research activity, market feedback of progress toward attainment of the objective is needed. Using the network of building experts available to the Building Thermal Envelope Systems and Materials program, a short mail survey was developed, administered, and results analyzed. This study concludes that foundation insulation usage on new residential buildings has increased from 1982 levels of around 25% to 1992 levels of around 50%. Government handbooks and recent changes in local enforced codes and standards are identified as major contributors to this improvement. Progress has been made but more is needed to capture the remaining 40% of the foundations that should be insulated. Several issues are reported as obstacles that need to be overcome to capture the remainder of the foundation market.

  16. A study of changes in foundation insulation levels in the United States

    SciTech Connect (OSTI)

    Christian, J.E. [Oak Ridge National Lab., TN (United States); Voss, M.K. [Saint Mary`s Coll., Winona, MN (United States)

    1992-10-01T23:59:59.000Z

    For almost 10 years the US Department of Energy (DOE) has sponsored a small research effort with. the objective of working with the building industry to see that cost-effective foundation insulation levels are installed in all US buildings. One of the first discoveries in 1983--1984 was that less than 5% of the existing buildings had foundation insulation and less than 30% of new construction included foundation insulation. After producing foundation handbooks, actively working with energy code and standards groups (ASHRAE and Council of American Building Officials: Model Energy Code Committee) conducting told experiments, and developing computer models for predicting energy savings has any measurable progress been made toward the fulfillment of this DOE objective? Also, in order to derive maximum energy savings impact for this ongoing research activity, market feedback of progress toward attainment of the objective is needed. Using the network of building experts available to the Building Thermal Envelope Systems and Materials program, a short mail survey was developed, administered, and results analyzed. This study concludes that foundation insulation usage on new residential buildings has increased from 1982 levels of around 25% to 1992 levels of around 50%. Government handbooks and recent changes in local enforced codes and standards are identified as major contributors to this improvement. Progress has been made but more is needed to capture the remaining 40% of the foundations that should be insulated. Several issues are reported as obstacles that need to be overcome to capture the remainder of the foundation market.

  17. Slab edge insulating form system and methods

    DOE Patents [OSTI]

    Lee, Brain E. (Corral de Tierra, CA); Barsun, Stephan K. (Davis, CA); Bourne, Richard C. (Davis, CA); Hoeschele, Marc A. (Davis, CA); Springer, David A. (Winters, CA)

    2009-10-06T23:59:59.000Z

    A method of forming an insulated concrete foundation is provided comprising constructing a foundation frame, the frame comprising an insulating form having an opening, inserting a pocket former into the opening; placing concrete inside the foundation frame; and removing the pocket former after the placed concrete has set, wherein the concrete forms a pocket in the placed concrete that is accessible through the opening. The method may further comprise sealing the opening by placing a sealing plug or sealing material in the opening. A system for forming an insulated concrete foundation is provided comprising a plurality of interconnected insulating forms, the insulating forms having a rigid outer member protecting and encasing an insulating material, and at least one gripping lip extending outwardly from the outer member to provide a pest barrier. At least one insulating form has an opening into which a removable pocket former is inserted. The system may also provide a tension anchor positioned in the pocket former and a tendon connected to the tension anchor.

  18. Excavationless Exterior Foundation Insulation Field Study

    SciTech Connect (OSTI)

    Schirber, T.; Mosiman, G.; Ojczyk, C.

    2014-10-01T23:59:59.000Z

    Building science research supports installing exterior (soil side) foundation insulation as the optimal method to enhance the hygrothermal performance of new homes. With exterior foundation insulation, water management strategies are maximized while insulating the basement space and ensuring a more even temperature at the foundation wall. However, such an approach can be very costly and disruptive when applied to an existing home, requiring deep excavation around the entire house. The NorthernSTAR Building America Partnership team implemented an innovative, minimally invasive foundation insulation upgrade technique on an existing home. The approach consisted of using hydrovac excavation technology combined with a liquid insulating foam. The team was able to excavate a continuous 4" wide by 4' to 5' deep trench around the entire house, 128 linear feet, except for one small part under the stoop that was obstructed with concrete debris. The combination pressure washer and vacuum extraction technology also enabled the elimination of large trenches and soil stockpiles normally produced by backhoe excavation. The resulting trench was filled with liquid insulating foam, which also served as a water-control layer of the assembly. The insulation was brought above grade using a liquid foam/rigid foam hybrid system and terminated at the top of the rim joist. Cost savings over the traditional excavation process ranged from 23% to 50%. The excavationless process could result in even greater savings since replacement of building structures, exterior features, utility meters, and landscaping would be minimal or non-existent in an excavationless process.

  19. Thermal synthesis apparatus

    DOE Patents [OSTI]

    Fincke, James R. (Idaho Falls, ID) [Idaho Falls, ID; Detering, Brent A. (Idaho Falls, ID) [Idaho Falls, ID

    2009-08-18T23:59:59.000Z

    An apparatus for thermal conversion of one or more reactants to desired end products includes an insulated reactor chamber having a high temperature heater such as a plasma torch at its inlet end and, optionally, a restrictive convergent-divergent nozzle at its outlet end. In a thermal conversion method, reactants are injected upstream from the reactor chamber and thoroughly mixed with the plasma stream before entering the reactor chamber. The reactor chamber has a reaction zone that is maintained at a substantially uniform temperature. The resulting heated gaseous stream is then rapidly cooled by passage through the nozzle, which "freezes" the desired end product(s) in the heated equilibrium reaction stage, or is discharged through an outlet pipe without the convergent-divergent nozzle. The desired end products are then separated from the gaseous stream.

  20. Radiative Heat Transfer in Enhanced Hydrogen Outgassing of Glass

    E-Print Network [OSTI]

    Kitamura, Rei; Pilon, Laurent

    2009-01-01T23:59:59.000Z

    Kaviany and B.P. Singh, “Radiative heat transfer in porousmedia”, Advances in Heat Transfer, vol. 23, no. 23, pp. 133–Thermal radiation heat transfer, Hemisphere Publishing Co. ,

  1. In-situ aging of roof systems containing polyisocyanurate roof insulation foamed with alternative blowing agents

    SciTech Connect (OSTI)

    Desjarlais, A.O.; Christian, J.E.; Graves, R.S.

    1993-10-01T23:59:59.000Z

    Experimental polyisocyanurate (PIR) foam roof insulations with permeable facers were installed in roofing systems and continuously monitored for thermal performance for four years. The foams were produced using a specific formulation that represented current technology in 1989 and were blown with CFC-11, HCFC-123, and HCFC-141b. These foams were installed in roof systems comprised of loosely-laid insulation boards covered by either a loosely-laid single ply white or black membrane. The in-situ testing was carried out on an outdoor test facility, the Roof Thermal Research Apparatus (RTRA). Additional specimens of these foams were aged in the laboratory and periodically evaluated using laboratory measurement equipment. This paper summarizes the in-situ data compiled to date, compares these data with the laboratory results, and examines whether the proposed laboratory procedure for accelerating the aging of foams by the slicing and scaling method accurately predicts the aging characteristics of these materials installed in roof systems. These experiments are part of a joint industry/government project established to evaluate the technical viability of alternative HCFC blowing agents for rigid closed-cell polyisocyanurate foam roof insulations. Members of the project are the US Department of Energy (DOE)/Oak Ridge National Laboratory (ORNL), the US Environmental Protection Agency (EPA), the Society of the Plastics Industry-Polyurethane Division (SPI), the Polyisocyanurate Insulation Manufacturers Association (PIMA), and the National Roofing Contractors Association (NRCA).

  2. Measure Guideline: Hybrid Foundation Insulation Retrofits

    SciTech Connect (OSTI)

    Ueno, K.; Lstiburek, J.

    2012-05-01T23:59:59.000Z

    This measure guideline provides recommendations for designs and variations for retrofit hybrid assemblies in improving interior foundation insulation and water management of basements. Variations include closed cell spray foam (ccSPF) with membrane waterproofing or air gap membrane drainage layers, rigid board foam insulation at flat walls (cast concrete or CMU block), a 'partial drainage' detail making use of the bulk water drainage that occurs through the field of a rubble stone wall, and non-drained spray foam assemblies (including slab insulation).

  3. 1 Introduction 3 2 Topological insulators -Overview 5

    E-Print Network [OSTI]

    Johannesson, Henrik

    Contents 1 Introduction 3 2 Topological insulators - Overview 5 2.1 Introduction quantum spin Hall insulator . . . . . . . . . . . . . 7 2.4 Three dimensional topological insulator . . . . . . . . . . . . . . . . 9 3 Bulk band structure in a 2D spin orbit induced topological insulator 11 3.1 Introduction

  4. Evaluation of Experimental Parameters in the Accelerated Aging of Closed-Cell Foam Insulation

    SciTech Connect (OSTI)

    Stovall, Therese K [ORNL; Vanderlan, Michael [ORNL; Atchley, Jerald Allen [ORNL

    2012-12-01T23:59:59.000Z

    The thermal conductivity of many closed-cell foam insulation products changes over time as production gases diffuse out of the cell matrix and atmospheric gases diffuse into the cells. Thin slicing has been shown to be an effective means of accelerating this process in such a way as to produce meaningful results. Efforts to produce a more prescriptive version of the ASTM C1303 standard test method led to the ruggedness test described here. This test program included the aging of full size insulation specimens for time periods of five years for direct comparison to the predicted results. Experimental parameters under investigation include: slice thickness, slice origin (at the surface or from the core of the slab), thin slice stack composition, product facings, original product thickness, product density, and product type. The test protocol has been completed and this report provides a detailed evaluation of the impact of the test parameters on the accuracy of the 5-year thermal conductivity prediction.

  5. Radiation-hard electrical coil and method for its fabrication

    DOE Patents [OSTI]

    Grieggs, R.J.; Blake, R.D.; Gac, F.D.

    1982-06-29T23:59:59.000Z

    A radiation-hard insulated electrical coil and method for making the same are disclosed. In accordance with the method, a conductor, preferably copper, is wrapped with an aluminum strip and then tightly wound into a coil. The aluminum-wrapped coil is then annealed to relax the conductor in the coiled configuration. The annealed coil is then immersed in an alkaline solution to dissolve the aluminum strip, leaving the bare conductor in a coiled configuration with all of the windings closely packed yet uniformly spaced from one another. The coil is then insulated with a refractory insulating material. In the preferred embodiment, the coil is insulated by coating it with a vitreous enamel and subsequently potting the enamelled coil in a castable ceramic concrete. The resulting coil is substantially insensitive to radiation and may be operated continuously in high radiation environments for long periods of time.

  6. Strained-Si-on-Insulator (SSOI) and SiGe-on-Insulator (SGOI): Fabrication Obstacles and Solutions

    E-Print Network [OSTI]

    Strained-Si-on-Insulator (SSOI) and SiGe-on-Insulator (SGOI): Fabrication Obstacles and Solutions-Si and SiGe-on-insulator were fabricated, combining both the benefits of high-mobility strained-Si and SOI) to oxidized handle wafers. Layer transfer onto insulating handle wafers can be accomplished using grind

  7. PHYSICAL REVIEW B 83, 165440 (2011) Electron interaction-driven insulating ground state in Bi2Se3 topological insulators

    E-Print Network [OSTI]

    Wang, Wei Hua

    2011-01-01T23:59:59.000Z

    topological insulators in the two-dimensional limit Minhao Liu,1 Cui-Zu Chang,1,2 Zuocheng Zhang,1 Yi Zhang,2 of ultrathin Bi2Se3 topological insulators with thickness from one quintuple layer to six quintuple layers that this unusual insulating ground state in the two-dimensional limit of topological insulators is induced

  8. Ultrathin Strained Si-on-Insulator and SiGe-on-Insulator Created using Low Temperature Wafer Bonding

    E-Print Network [OSTI]

    Ultrathin Strained Si-on-Insulator and SiGe-on-Insulator Created using Low Temperature Wafer, uniform thickness, low defect density, monocrystalline SiGe alloys and strained Si on any desired substrate was developed, allowing for the creation of SiGe-on-insulator and strained Si-on-insulator. After

  9. Thermal Performance Evaluation of Innovative Metal Building Roof Assemblies

    SciTech Connect (OSTI)

    Walker, Daniel James [ORNL; Zaltash, Abdolreza [ORNL; Atchley, Jerald Allen [ORNL

    2011-01-01T23:59:59.000Z

    In order to meet the coming energy codes, multiple layers of various insulation types will be required. The demand for greater efficiency has pushed insulation levels beyond the cavity depth. These experiments show the potential for improving metal building roof thermal performance. Additional work is currently being done by several stakeholders, so the data is expanding. These experiments are for research and development purposes, and may not be viable for immediate use.

  10. Nonlinear boundary value problem of magnetic insulation

    E-Print Network [OSTI]

    A. V. Sinitsyn

    2000-09-09T23:59:59.000Z

    On the basis of generalization of upper and lower solution method to the singular two point boundary value problems, the existence theorem of solutions for the system, which models a process of magnetic insulation in plasma is proved.

  11. Metal-insulator transition in holography

    E-Print Network [OSTI]

    Aristomenis Donos; Sean A. Hartnoll

    2013-01-19T23:59:59.000Z

    We exhibit an interaction-driven metal-insulator quantum phase transition in a holographic model. Use of a helical lattice enables us to break translation invariance while preserving homogeneity. The metallic phase is characterized by a sharp Drude peak and a d.c. resistivity that increases with temperature. In the insulating phase the Drude spectral weight is transferred into a `mid-infrared' peak and to energy scales of order the chemical potential. The d.c. resistivity now decreases with temperature. In the metallic phase, operators breaking translation invariance are irrelevant at low energy scales. In the insulating phase, translation symmetry breaking effects are present at low energies. We find the near horizon extremal geometry that captures the insulating physics.

  12. Phosphorylation based insulation devices design and implementation

    E-Print Network [OSTI]

    Rivera Ortiz, Phillip M. (Phillip Michael)

    2013-01-01T23:59:59.000Z

    This thesis presents the analysis of a phosphorylation based insulation device implemented in Saccharomyces cerevisae and the minimization of the retroactivity to the input and retroactivity to the output of a single cycle ...

  13. Install Removable Insulation on Valves and Fittings

    SciTech Connect (OSTI)

    Not Available

    2006-01-01T23:59:59.000Z

    This revised ITP tip sheet on installing removable insulation on valves and fittings provides how-to advice for improving the system using low-cost, proven practices and technologies.

  14. Saving Energy and Money with Aerogel Insulation

    Broader source: Energy.gov [DOE]

    The Energy Department is investing in an innovative insulation material that saves energy and money for industrial facilities while also helping to support 50 full-time clean energy jobs for Americans.

  15. KSI's Cross Insulated Core Transformer Technology

    SciTech Connect (OSTI)

    Uhmeyer, Uwe [Kaiser Systems, Inc, 126 Sohier Road, Beverly, MA 01915 (United States)

    2009-08-04T23:59:59.000Z

    Cross Insulated Core Transformer (CCT) technology improves on Insulated Core Transformer (ICT) implementations. ICT systems are widely used in very high voltage, high power, power supply systems. In an ICT transformer ferrite core sections are insulated from their neighboring ferrite cores. Flux leakage is present at each of these insulated gaps. The flux loss is raised to the power of stages in the ICT design causing output voltage efficiency to taper off with increasing stages. KSI's CCT technology utilizes a patented technique to compensate the flux loss at each stage of an ICT system. Design equations to calculate the flux compensation capacitor value are presented. CCT provides corona free operation of the HV stack. KSI's CCT based High Voltage power supply systems offer high efficiency operation, high frequency switching, low stored energy and smaller size over comparable ICT systems.

  16. Probing the topology in band insulators

    E-Print Network [OSTI]

    Chen, Kuang-Ting, Ph. D. Massachusetts Institute of Technology

    2012-01-01T23:59:59.000Z

    Topological Insulator is a newly found state of matter. Unlike phases described by the traditional Landau theory of symmetry breaking, the topological phases do not break symmetry, and it is not obvious in which measurable ...

  17. Air leakage of Insulated Concrete Form houses

    E-Print Network [OSTI]

    Durschlag, Hannah (Hanna Rebekah)

    2012-01-01T23:59:59.000Z

    Air leakage has been shown to increase building energy use due to additional heating and cooling loads. Although many construction types have been examined for leakage, an exploration of a large number of Insulated Concrete ...

  18. A Guide to Insulation Selection for Industrial Applications

    E-Print Network [OSTI]

    Harrison, M. R.

    1979-01-01T23:59:59.000Z

    of new insulations on th mar ket, it is important that the insulation selection process be upgraded. Insulation peci fications need to be reviewed in terms of new products and installation techniques. Also, the specific application or end use should... be critically analyzed to determine whic~ pro f ducts are best suited for that application. INSULATION MATERIAL SELECTION The selection and specification of insulation materials can be broken down int two I separate but interrelated activities. The first...

  19. Panelized wall system with foam core insulation

    DOE Patents [OSTI]

    Kosny, Jan (Oak Ridge, TN); Gaskin, Sally (Houston, TX)

    2009-10-20T23:59:59.000Z

    A wall system includes a plurality of wall members, the wall members having a first metal panel, a second metal panel, and an insulating core between the first panel and the second panel. At least one of the first panel and the second panel include ridge portions. The insulating core can be a foam, such as a polyurethane foam. The foam can include at least one opacifier to improve the k-factor of the foam.

  20. T-Duality and Topological Insulators

    E-Print Network [OSTI]

    Mathai, Varghese

    2015-01-01T23:59:59.000Z

    It is well known that topological insulators are classified by a family of groups, which coincidentally also classifies D-brane charges on orientifolds in string theory. In this letter, we extend this correlation via a geometric analog of the real Fourier transform to obtain a novel duality of topological insulators that can be viewed as a condensed matter analog of T-duality in string theory.

  1. Status of surface conduction in topological insulators

    SciTech Connect (OSTI)

    Barua, Sourabh, E-mail: sbarua@iitk.ac.in; Rajeev, K. P. [Department of Physics, Indian Institute of Technology Kanpur, Kanpur 208016 (India)] [Department of Physics, Indian Institute of Technology Kanpur, Kanpur 208016 (India)

    2014-01-15T23:59:59.000Z

    In this report, we scrutinize the thickness dependent resistivity data from the recent literature on electrical transport measurements in topological insulators. A linear increase in resistivity with increase in thickness is expected in the case of these materials since they have an insulating bulk and a conducting surface. However, such a trend is not seen in the resistivity versus thickness data for all the cases examined, except for some samples, where it holds for a range of thickness.

  2. Numerical Simulation of Thermal Performance of Floor Radiant Heating System with Enclosed Phase Change Material

    E-Print Network [OSTI]

    Qiu, L.; Wu, X.

    2006-01-01T23:59:59.000Z

    water temperatures. With the method of enthalpy , the PCM thermal storage time is studied under different supply water temperatures, supply water flows, distances between water wipe in the floor construction, floor covers and insulation conditions....

  3. Planar jumping-drop thermal diodes Jonathan B. Boreyko, Yuejun Zhao, and Chuan-Hua Chena)

    E-Print Network [OSTI]

    Chen, Chuan-Hua

    plates (Fig. 1). The plates are separated by a thermally insulating gasket which also provides a vacuum of asymmetric heat pipes into a wall panel solves the dimen- sionality problem but results in an order

  4. Topological insulators and superconductors from string theory

    SciTech Connect (OSTI)

    Ryu, Shinsei; Takayanagi, Tadashi [Department of Physics, University of California, Berkeley, California 94720 (United States); Institute for the Physics and Mathematics of the Universe (IPMU), University of Tokyo, Kashiwa, Chiba 277-8582 (Japan)

    2010-10-15T23:59:59.000Z

    Topological insulators and superconductors in different spatial dimensions and with different discrete symmetries have been fully classified recently, revealing a periodic structure for the pattern of possible types of topological insulators and superconductors, both in terms of spatial dimensions and in terms of symmetry classes. It was proposed that K theory is behind the periodicity. On the other hand, D-branes, a solitonic object in string theory, are also known to be classified by K theory. In this paper, by inspecting low-energy effective field theories realized by two parallel D-branes, we establish a one-to-one correspondence between the K-theory classification of topological insulators/superconductors and D-brane charges. In addition, the string theory realization of topological insulators and superconductors comes naturally with gauge interactions, and the Wess-Zumino term of the D-branes gives rise to a gauge field theory of topological nature, such as ones with the Chern-Simons term or the {theta} term in various dimensions. This sheds light on topological insulators and superconductors beyond noninteracting systems, and the underlying topological field theory description thereof. In particular, our string theory realization includes the honeycomb lattice Kitaev model in two spatial dimensions, and its higher-dimensional extensions. Increasing the number of D-branes naturally leads to a realization of topological insulators and superconductors in terms of holography (AdS/CFT).

  5. Topological Insulators and Superconductors from String Theory

    E-Print Network [OSTI]

    Shinsei Ryu; Tadashi Takayanagi

    2010-08-01T23:59:59.000Z

    Topological insulators and superconductors in different spatial dimensions and with different discrete symmetries have been fully classified recently, revealing a periodic structure for the pattern of possible types of topological insulators and supercondutors, both in terms of spatial dimensions and in terms of symmetry classes. It was proposed that K-theory is behind the periodicity. On the other hand, D-branes, a solitonic object in string theory, are also known to be classified by K-theory. In this paper, by inspecting low-energy effective field theories realized by two parallel D-branes, we establish a one-to-one correspondence between the K-theory classification of topological insulators/superconductors and D-brane charges. In addition, the string theory realization of topological insulators and superconductors comes naturally with gauge interactions, and the Wess-Zumino term of the D-branes gives rise to a gauge field theory of topological nature, such as ones with the Chern-Simons term or the $\\theta$-term in various dimensions. This sheds light on topological insulators and superconductors beyond non-interacting systems, and the underlying topological field theory description thereof. In particular, our string theory realization includes the honeycomb lattice Kitaev model in two spatial dimensions, and its higher-dimensional extensions. Increasing the number of D-branes naturally leads to a realization of topological insulators and superconductors in terms of holography (AdS/CFT).

  6. Solar Thermal Conversion

    SciTech Connect (OSTI)

    Kreith, F.; Meyer, R. T.

    1982-11-01T23:59:59.000Z

    The thermal conversion process of solar energy is based on well-known phenomena of heat transfer (Kreith 1976). In all thermal conversion processes, solar radiation is absorbed at the surface of a receiver, which contains or is in contact with flow passages through which a working fluid passes. As the receiver heats up, heat is transferred to the working fluid which may be air, water, oil, or a molten salt. The upper temperature that can be achieved in solar thermal conversion depends on the insolation, the degree to which the sunlight is concentrated, and the measures taken to reduce heat losses from the working fluid.

  7. Magnetic insulation at finite temperatures

    SciTech Connect (OSTI)

    Goedecke, G. H.; Davis, Brian T.; Chen, Chiping [Physics Department, New Mexico State University, Las Cruces, New Mexico 88003 and Raytheon Missile Systems, 1151 E. Hermans Road, Tucson, Arizona 85706 (United States); Intense Beam Theoretical Research Group, Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 and Raytheon Missile Systems, 1151 E. Hermans Road, Tucson, Arizona 85706 (United States)

    2006-08-15T23:59:59.000Z

    A finite-temperature non-neutral plasma (FTNNP) theory of magnetically insulated (MI) electron flows in crossed-field vacuum devices is developed and applied in planar geometry. It is shown that, in contrast to the single type of MI flow predicted by traditional cold-plasma treatments, the nonlinear FTNNP equations admit five types of steady flow, of which three types are MI flows, including flows in which the electric field and/or the tangential velocity at the cathode may be zero or nonzero. It is also shown that finite-temperature Vlasov-Poisson treatments yield solutions for electron number densities and electrostatic potentials that are a subset of the FTNNP solutions. The algorithms that are used to solve the FTNNP equations numerically are discussed, and the numerical results are presented for several examples of the three types of MI flow. Results include prediction of the existence, boundaries, number density profiles, and other properties of sheaths of electrons in the anode-cathode gap.

  8. Effects of thermal radiation heat transfer on flame acceleration and transition to detonation in dust cloud flames: Origins of dust explosion

    E-Print Network [OSTI]

    Ivanov, Michael A Liberman M F

    2015-01-01T23:59:59.000Z

    We examines regimes of the hydrogen flames propagation and ignition of mixtures heated by the radiation emitted from the flame. The gaseous phase is assumed to be transparent for radiation, while the suspended particles of the dust cloud ahead of the flame absorb and reemit the radiation. The radiant heat absorbed by the particles is then lost by conduction to the surrounding unreacted gaseous phase so that the gas phase temperature lags that of the particles. The direct numerical simulations solve the full system of two phase gas dynamic time-dependent equations with a detailed chemical kinetics for a plane flames propagating through a dust cloud. Depending on the spatial distribution of the dispersed particles and on the value of radiation absorption length the consequence of the radiative preheating of the unreacted mixture can be either the increase of the flame velocity for uniformly dispersed particles or ignition deflagration or detonation ahead of the flame via the Zel'dovich gradient mechanism in the...

  9. Performance of Titanium-Oxide/Polymer Insulation in Bi-2212/Ag-alloy Round Wire Wound Superconducting Coils

    E-Print Network [OSTI]

    Peng Chen; Ulf P Trociewitz; Matthieu Dalban-Canassy; Jianyi Jiang; Eric E Hellstrom; David C Larbalestier

    2013-03-20T23:59:59.000Z

    Conductor insulation is one of the key components needed to make Ag-alloy clad Bi2Sr2CaCu2O8+x (Bi-2212/Ag) superconducting round wire (RW) successful for high field magnet applications as dielectric standoff and high winding current densities (Jw) directly depend on it. In this study, a TiO2/polymer insulation coating developed by nGimat LLC was applied to test samples and a high field test coil. The insulation was investigated by differential thermal analysis (DTA), thermo-gravimetric analysis (TGA), scanning electron microscopy (SEM), dielectric properties measurement, and transport critical current (Ic) properties measurement. About 29% of the insulation by weight is polymer. When the Bi-2212/Ag wire is full heat treated, this decomposes with slow heating to 400{\\deg}C in pure O2. After the full reaction, we found that the TiO2 did not degrade the critical current properties, adhered well to the conductor, and provided a breakdown voltage of >100 V, which allowed the test coil to survive quenching in 31.2 T background field, while providing a 2.6 T field increment. For Bi-2212/Ag RW with a typical diameter of 1.0-1.5 mm, this ~15 um thick insulation allows a very high coil packing factor of ~0.74, whereas earlier alumino-silicate braid insulation only allows packing factors of 0.38-0.48.

  10. Non-CFC vacuum alternatives for the energy-efficient insulation of household refrigerators: Design and use

    SciTech Connect (OSTI)

    Potter, T.F.; Benson, D.K.

    1991-01-01T23:59:59.000Z

    Energy efficiency, environmental issues, and market incentives all encourage government and industry to continue work on thin-profile vacuum insulations for domestic refrigerators and freezers (R/Fs). Vacuum insulations promise significant improvement in thermal savings over current insulations; the technical objective of one design is an R-value of better than 10 (hr-ft{sup 2}-F/Btu) in 0.1 in. thickness. If performance is improved by a factor of 10 over that of CFC-blown insulating foams, the new insulations (made without CFCs or other potentially troublesome fill gases) will change the design and improve the efficiency of refrigerators. Such changes will meet the conservation, regulatory, and market drivers now strong in developed countries and likely to increase in developing countries. Prototypes of various designs have been tested in the laboratory and in factories, and results to date confirm the good thermal performance of these thin-profile alternatives. The next step is to resolve issues of reliability and cost effectiveness. 34 refs., 4 figs.

  11. Thermal Analyses Thermal Resistance of Precast Concrete Wall Panels with Concrete

    E-Print Network [OSTI]

    Meyer, Christian

    ) analyses. 3-D analyses are more accurate since the concrete ribs act as thermal bridges to both horizontal considered are as follows: · cavity insulation thickness · concrete conductivity · stud channel conductivity channel increases too. The cavity R-value is calculated by ignoring the effect of the concrete web. Assume

  12. Insulation of steel studs in the rehab of masonry structures

    SciTech Connect (OSTI)

    Ide, N.F. [Grass Roots Alliance for a Solar Pennsylvania, Philadelphia, PA (United States); Larson, D.C.; Abdou, O.A. [Drexel Univ., Philadelphia, PA (United States)

    1998-10-01T23:59:59.000Z

    Metal studs cause thermal bridging when erected next to existing masonry walls. To mitigate this thermal bridge, the authors propose to move the studs away from the masonry and install thicker batt to fill the entire cavity. This experiment addresses two questions: (1) How much does R-value improve when using batt this is thicker than the studs;? (2) How much do gaps between batts degrade this improved R-value? A 4 ft (1.22 m) square test wall was constructed with a 5.25 in. (133 mm) deep cavity. Steel studs, spaced 16 in. (406 mm) on center, were set 1.75 in. (44 mm) away from the masonry (simulated by gypsum). Three insulation configurations were tested using a scanning heat flux meter. Clear-wall R-values were calculated from the heat flux profile across the center stud cavity. The base case used R-11 batt (R{sub SI}-1.94) and yielded R-8.5 (1.50). Completely filling the cavity with batt having an installed thermal resistance of R-17.2 (3.03) improved the R-value to R-14.2 (2.50). Introducing gaps the width of the studs decreased the R-value to R-12.8 (2.25). The apparatus was calibrated against a transfer standard obtained from National Institute of Standards and Technology (NIST).

  13. Method for minimizing contaminant particle effects in gas-insulated electrical apparatus

    DOE Patents [OSTI]

    Pace, Marshall O. (Knoxville, TN); Adcock, James L. (Knoxville, TN); Christophorou, Loucas G. (Oak Ridge, TN)

    1984-01-01T23:59:59.000Z

    Electrical breakdown of a gas insulator in high voltage apparatus is preved by placing an electrical insulative coating on contaminant particles in the gas insulator.

  14. Dynamic predictive clothing insulation models based on outdoor air and indoor operative temperatures

    E-Print Network [OSTI]

    Schiavon, Stefano; Lee, Kwang Ho

    2012-01-01T23:59:59.000Z

    predictive clothing insulation models based on outdoor airrange of the clothing insulation calculated for eachbuilding). Figure 8 Clothing insulation versus dress code [

  15. Influence of two dynamic predictive clothing insulation models on building energy performance

    E-Print Network [OSTI]

    Lee, Kwang Ho; Schiavon, Stefano

    2013-01-01T23:59:59.000Z

    Predictive Clothing Insulation Models on Building Energyunnecessarily higher clothing insulation and lower heatingthat the constant clothing insulation assumption lead to the

  16. Predictive clothing insulation model based on outdoor air and indoor operative temperatures

    E-Print Network [OSTI]

    Schiavon, Stefano; Lee, Kwang Ho

    2012-01-01T23:59:59.000Z

    2012) Predictive clothing insulation model based on outdoorPredictive clothing insulation model based on outdoor airpredictive models of clothing insulation have been developed

  17. Efficient Phase-Change Materials: Development of a Low-Cost Thermal Energy Storage System Using Phase-Change Materials with Enhanced Radiation Heat Transfer

    SciTech Connect (OSTI)

    None

    2011-12-05T23:59:59.000Z

    HEATS Project: USF is developing low-cost, high-temperature phase-change materials (PCMs) for use in thermal energy storage systems. Heat storage materials are critical to the energy storage process. In solar thermal storage systems, heat can be stored in these materials during the day and released at night—when the sun is not out—to drive a turbine and produce electricity. In nuclear storage systems, heat can be stored in these materials at night and released to produce electricity during daytime peak-demand hours. Most PCMs do not conduct heat very well. Using an innovative, electroless encapsulation technique, USF is enhancing the heat transfer capability of its PCMs. The inner walls of the capsules will be lined with a corrosion-resistant, high-infrared emissivity coating, and the absorptivity of the PCM will be controlled with the addition of nano-sized particles. USF’s PCMs remain stable at temperatures from 600 to 1,000°C and can be used for solar thermal power storage, nuclear thermal power storage, and other applications.

  18. An Insulating Glass Knowledge Base

    SciTech Connect (OSTI)

    Michael L. Doll; Gerald Hendrickson; Gerard Lagos; Russell Pylkki; Chris Christensen; Charlie Cureija

    2005-08-01T23:59:59.000Z

    This report will discuss issues relevant to Insulating Glass (IG) durability performance by presenting the observations and developed conclusions in a logical sequential format. This concluding effort discusses Phase II activities and focuses on beginning to quantifying IG durability issues while continuing the approach presented in the Phase I activities (Appendix 1) which discuss a qualitative assessment of durability issues. Phase II developed a focus around two specific IG design classes previously presented in Phase I of this project. The typical box spacer and thermoplastic spacer design including their Failure Modes and Effect Analysis (FMEA) and Fault Tree diagrams were chosen to address two currently used IG design options with varying components and failure modes. The system failures occur due to failures of components or their interfaces. Efforts to begin quantifying the durability issues focused on the development and delivery of an included computer based IG durability simulation program. The focus/effort to deliver the foundation for a comprehensive IG durability simulation tool is necessary to address advancements needed to meet current and future building envelope energy performance goals. This need is based upon the current lack of IG field failure data and the lengthy field observation time necessary for this data collection. Ultimately, the simulation program is intended to be used by designers throughout the current and future industry supply chain. Its use is intended to advance IG durability as expectations grow around energy conservation and with the growth of embedded technologies as required to meet energy needs. In addition the tool has the immediate benefit of providing insight for research and improvement prioritization. Included in the simulation model presentation are elements and/or methods to address IG materials, design, process, quality, induced stress (environmental and other factors), validation, etc. In addition, acquired data is presented in support of project and model assumptions. Finally, current and suggested testing protocol and procedure for future model validation and IG physical testing are discussed.

  19. Topological insulators and topological nonlinear {sigma} models

    SciTech Connect (OSTI)

    Yao Hong; Lee, Dung-Hai [Department of Physics, University of California at Berkeley, Berkeley, California 94720 (United States) and Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)

    2010-12-15T23:59:59.000Z

    In this paper we link the physics of topological nonlinear {sigma} models with that of Chern-Simons insulators. We show that corresponding to every 2n-dimensional Chern-Simons insulator there is a (n-1)-dimensional topological nonlinear {sigma} model with the Wess-Zumino-Witten term. Breaking internal symmetry in these nonlinear {sigma} models leads to nonlinear {sigma} models with the {theta} term. [This is analogous to the dimension reduction leading from 2n-dimensional Chern-Simons insulators to (2n-1) and (2n-2)-dimensional topological insulators protected by discrete symmetries.] The correspondence described in this paper allows one to derive the topological term in a theory involving fermions and order parameters (we shall referred to them as ''fermion-{sigma} models'') when the conventional gradient-expansion method fails. We also discuss the quantum number of solitons in topological nonlinear {sigma} model and the electromagnetic action of the (2n-1)-dimensional topological insulators. Throughout the paper we use a simple model to illustrate how things work.

  20. Thermal transport in boron nitride nanotorus—towards a nanoscopic thermal shield

    SciTech Connect (OSTI)

    Loh, G. C., E-mail: jgloh@mtu.edu [Institute of High Performance Computing, 1 Fusionopolis Way, 16-16 Connexis, Singapore 138632 (Singapore); Department of Physics, Michigan Technological University, Houghton, Michigan 49931 (United States); Baillargeat, D. [CNRS-International-NTU-Thales Research Alliance (CINTRA), 50 Nanyang Drive, Singapore 637553 (Singapore)

    2013-11-14T23:59:59.000Z

    Nanotori, or nanorings, are topological variants of nanotubes and are conceived to have different properties from their tubular form. In this study, the toroidal arrangement of boron nitride is introduced. Using classical molecular dynamics simulations, the thermal behaviour (thermal conductivity and thermal stability) of the boron nitride nanotorus and its relationship with the structural characteristics are investigated. Its circumferential thermal rectification strength displays a linear dependence on the bending coefficient of the nanostructure. Surface kinks are relatively inconsequential on its circumferential mode of conduction, as compared to its axial sense. The circumferential conductivity in the diffusive regime is calculated to be approximately 10?W/m K, while the axial conductivity is more than tenfold of this value. All nanotori with different toroidal characters show excellent thermal stability at extremely high temperatures approaching 3400?K. With consideration to its favourable properties, a thermal shield made up of a parallel row of nanotori is proposed as a nanoscale thermal insulation device.

  1. Affordable Cold Climate Infill Housing with Hybrid Insulation Approach, Wyandotte, Michigan (Fact Sheet)

    SciTech Connect (OSTI)

    Metzger, C.; Lukachko, A.; Grin, A.; Bergey, D.

    2013-11-01T23:59:59.000Z

    Even builders who are relatively new to energy-efficient construction can consistently reach a target whole house airtightness of 1.5 air changes per hour at 50 Pascals (ACH50) with high R-value enclosures that use a hybrid insulation approach. The City of Wyandotte, Michigan, started a construction program in 2010 to build affordable, energy-efficient homes on lots in existing neighborhoods. A goal of the program was to engage local builders in energy-efficient construction and be able to deliver the new houses for less than $100/ft2. By the end of 2012, approximately 25 new houses were built by five local builders under this program. To help builders consistently achieve the airtightness target, a local architect worked with researchers from Building Science Corporation, a U.S. Department of Energy Building America team, to develop a technology specification with several key pieces. A high R-value wall and roof assembly made use of 2 ?6 advanced framing and a hybrid insulation approach that included insulating sheathing to control thermal bridging and closed cell spray polyurethane foam insulation (ccSPF) for its airtightness and vapor control benefits. This approach allows the air barrier to be completed and tested before any finishing work occurs, ensuring that problems are spotted and corrected early in the construction process.

  2. Nuclear reactor having a polyhedral primary shield and removable vessel insulation

    DOE Patents [OSTI]

    Ekeroth, D.E.; Orr, R.

    1993-12-07T23:59:59.000Z

    A nuclear reactor is provided having a generally cylindrical reactor vessel disposed within an opening in a primary shield. The opening in the primary shield is defined by a plurality of generally planar side walls forming a generally polyhedral-shaped opening. The reactor vessel is supported within the opening in the primary shield by reactor vessel supports which are in communication and aligned with central portions of some of the side walls. The reactor vessel is connected to the central portions of the reactor vessel supports. A thermal insulation polyhedron formed from a plurality of slidably insertable and removable generally planar insulation panels substantially surrounds at least a portion of the reactor vessel and is disposed between the reactor vessel and the side walls of the primary shield. The shape of the insulation polyhedron generally corresponds to the shape of the opening in the primary shield. Reactor monitoring instrumentation may be mounted in the corners of the opening in the primary shield between the side walls and the reactor vessel such that insulation is not disposed between the instrumentation and the reactor vessel. 5 figures.

  3. Nuclear reactor having a polyhedral primary shield and removable vessel insulation

    DOE Patents [OSTI]

    Ekeroth, Douglas E. (Delmont, PA); Orr, Richard (Pittsburgh, PA)

    1993-01-01T23:59:59.000Z

    A nuclear reactor is provided having a generally cylindrical reactor vessel disposed within an opening in a primary shield. The opening in the primary shield is defined by a plurality of generally planar side walls forming a generally polyhedral-shaped opening. The reactor vessel is supported within the opening in the primary shield by reactor vessel supports which are in communication and aligned with central portions of some of the side walls. The reactor vessel is connected to the central portions of the reactor vessel supports. A thermal insulation polyhedron formed from a plurality of slidably insertable and removable generally planar insulation panels substantially surrounds at least a portion of the reactor vessel and is disposed between the reactor vessel and the side walls of the primary shield. The shape of the insulation polyhedron generally corresponds to the shape of the opening in the primary shield. Reactor monitoring instrumentation may be mounted in the corners of the opening in the primary shield between the side walls and the reactor vessel such that insulation is not disposed between the instrumentation and the reactor vessel.

  4. Initial and Long-Term Movement of Cladding Installed Over Exterior Rigid Insulation

    SciTech Connect (OSTI)

    Baker, P.

    2014-09-01T23:59:59.000Z

    Changes in the International Energy Conservation Code (IECC) from 2009 to 2012 have resulted in the use of exterior rigid insulation becoming part of the prescriptive code requirements. With more jurisdictions adopting the 2012 IECC builders are going to finding themselves required to incorporate exterior insulation in the construction of their exterior wall assemblies. For thick layers of exterior insulation (levels greater than 1.5 inches), the use wood furring strips attached through the insulation back to the structure has been used by many contractors and designers as a means to provide a convenient cladding attachment location. However, there has been a significant resistance to its widespread implementation due to a lack of research and understanding of the mechanisms involved and potential creep effects of the assembly under the sustained dead load of a cladding. This research was an extension on previous research conducted by BSC in 2011, and 2012. Each year the understanding of the system discrete load component interactions, as well as impacts of environmental loading has increased. The focus of the research was to examine more closely the impacts of screw fastener bending on the total system capacity, effects of thermal expansion and contraction of materials on the compressive forces in the assembly, as well as to analyze a full years worth of cladding movement data from assemblies constructed in an exposed outdoor environment.

  5. High thermal conductivity lossy dielectric using a multi layer configuration

    DOE Patents [OSTI]

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

    2003-01-01T23:59:59.000Z

    Systems and methods are described for loss dielectrics. A loss dielectric includes at least one high dielectric loss layer and at least one high thermal conductivity-electrically insulating layer adjacent the at least one high dielectric loss layer. A method of manufacturing a loss dielectric includes providing at least one high dielectric loss layer and providing at least one high thermal conductivity-electrically insulating layer adjacent the at least one high dielectric loss layer. The systems and methods provide advantages because the loss dielectrics are less costly and more environmentally friendly than the available alternatives.

  6. Gaseous insulators for high voltage electrical equipment

    DOE Patents [OSTI]

    Christophorou, Loucas G. (Oak Ridge, TN); James, David R. (Knoxville, TN); Pace, Marshall O. (Knoxville, TN); Pai, Robert Y. (Concord, TN)

    1981-01-01T23:59:59.000Z

    Gaseous insulators comprise compounds having high attachment cross sections for electrons having energies in the 0-1.3 electron volt range. Multi-component gaseous insulators comprise compounds and mixtures having overall high electron attachment cross sections in the 0-1.3 electron volt range and moderating gases having high cross sections for inelastic interactions with electrons of energies 1-4 electron volts. Suitable electron attachment components include hexafluorobutyne, perfluorobutene-2, perfluorocyclobutane, perfluorodimethylcyclobutane, perfluorocyclohexene, perfluoromethylcyclohexane, hexafluorobutadiene, perfluoroheptene-1 and hexafluoroazomethane. Suitable moderating gases include N.sub.2, CO, CO.sub.2 and H.sub.2. The gaseous insulating mixture can also contain SF.sub.6, perfluoropropane and perfluorobenzene.

  7. Is graphene in vacuum an insulator?

    E-Print Network [OSTI]

    Joaquín E. Drut; Timo A. Lähde

    2009-01-15T23:59:59.000Z

    We present evidence, from Lattice Monte Carlo simulations of the phase diagram of graphene as a function of the Coulomb coupling between quasiparticles, that graphene in vacuum is likely to be an insulator. We find a semimetal-insulator transition at $\\alpha_g^\\text{crit} = 1.11 \\pm 0.06$, where $\\alpha_g^{} \\simeq 2.16$ in vacuum, and $\\alpha_g^{} \\simeq 0.79$ on a SiO$_2^{}$ substrate. Our analysis uses the logarithmic derivative of the order parameter, supplemented by an equation of state. The insulating phase disappears above a critical number of four-component fermion flavors $4 < N_f^{\\text{crit}} < 6$. Our data are consistent with a second-order transition.

  8. Constraints on topological order in Mott Insulators

    E-Print Network [OSTI]

    Michael P. Zaletel; Ashvin Vishwanath

    2015-04-18T23:59:59.000Z

    We point out certain symmetry induced constraints on topological order in Mott Insulators (quantum magnets with an odd number of spin $\\tfrac{1}{2}$ per unit cell). We show, for example, that the double semion topological order is incompatible with time reversal and translation symmetry in Mott insulators. This sharpens the Hastings-Oshikawa-Lieb-Schultz-Mattis theorem for 2D quantum magnets, which guarantees that a fully symmetric gapped Mott insulator must be topologically ordered, but is silent on which topological order is permitted. An application of our result is the Kagome lattice quantum antiferromagnet where recent numerical calculations of entanglement entropy indicate a ground state compatible with either toric code or double semion topological order. Our result rules out the latter possibility.

  9. Insulation spacer eliminates electric shorts between lines

    SciTech Connect (OSTI)

    Colaizzi, J.F.; Rockafellow, G.B.

    1983-03-01T23:59:59.000Z

    The design criteria incorporated into the pipeline insulating spacer were: spacer material selected must have a very large compressive and tensile strength in order to withstand the weight and stress resulting on the pipelines; provide the necessary abrasive resistance, dielectric strength, and will not decay underground; must not soften with heat when used around or near stream lines or will not cold flow under pressure; minimum length and circumference to reduce ''Shielding Effects'' from any cathodic protection system; and provide a material that incorporates a maximum strength at a minimum thickness. Explains that electric shorts are caused by 2 or more metallic structures in contact with each other. Notes that the insulating spacer's use has been expanded to provide electrical and physical insulation between carrier pipe and casing, supports for piping in compressing stations, and for pipelines that are suspended on bridges.

  10. LOW TEMPERATURE PHYSICS RADIATION EFFECTS ON

    E-Print Network [OSTI]

    McDonald, Kirk

    LOW TEMPERATURE PHYSICS RADIATION EFFECTS ON FUSION MAGNET COMPONENTS Harald W. Weber Vienna Stabilizer Insulation Conclusions ESS, 4th High Power Targetry Workshop, Malmö 5 May 2011 #12;LOW TEMPERATURE PHYSICS Overview: ITER 300-500 s INTRODUCTION #12;LOW TEMPERATURE PHYSICS ITER Magnet System (5 K / 6.5 K

  11. Silicon on insulator with active buried regions

    DOE Patents [OSTI]

    McCarthy, Anthony M. (Menlo Park, CA)

    1998-06-02T23:59:59.000Z

    A method for forming patterned buried components, such as collectors, sources and drains, in silicon-on-insulator (SOI) devices. The method is carried out by epitaxially growing a suitable sequence of single or multiple etch stop layers ending with a thin silicon layer on a silicon substrate, masking the silicon such that the desired pattern is exposed, introducing dopant and activating in the thin silicon layer to form doped regions. Then, bonding the silicon layer to an insulator substrate, and removing the silicon substrate. The method additionally involves forming electrical contact regions in the thin silicon layer for the buried collectors.

  12. Silicon on insulator with active buried regions

    DOE Patents [OSTI]

    McCarthy, A.M.

    1996-01-30T23:59:59.000Z

    A method is disclosed for forming patterned buried components, such as collectors, sources and drains, in silicon-on-insulator (SOI) devices. The method is carried out by epitaxially growing a suitable sequence of single or multiple etch stop layers ending with a thin silicon layer on a silicon substrate, masking the silicon such that the desired pattern is exposed, introducing dopant and activating in the thin silicon layer to form doped regions. Then, bonding the silicon layer to an insulator substrate, and removing the silicon substrate. The method additionally involves forming electrical contact regions in the thin silicon layer for the buried collectors. 10 figs.

  13. Silicon on insulator with active buried regions

    DOE Patents [OSTI]

    McCarthy, Anthony M. (Menlo Park, CA)

    1996-01-01T23:59:59.000Z

    A method for forming patterned buried components, such as collectors, sources and drains, in silicon-on-insulator (SOI) devices. The method is carried out by epitaxially growing a suitable sequence of single or multiple etch stop layers ending with a thin silicon layer on a silicon substrate, masking the silicon such that the desired pattern is exposed, introducing dopant and activating in the thin silicon layer to form doped regions. Then, bonding the silicon layer to an insulator substrate, and removing the silicon substrate. The method additionally involves forming electrical contact regions in the thin silicon layer for the buried collectors.

  14. Silicon on insulator with active buried regions

    DOE Patents [OSTI]

    McCarthy, A.M.

    1998-06-02T23:59:59.000Z

    A method is disclosed for forming patterned buried components, such as collectors, sources and drains, in silicon-on-insulator (SOI) devices. The method is carried out by epitaxially growing a suitable sequence of single or multiple etch stop layers ending with a thin silicon layer on a silicon substrate, masking the silicon such that the desired pattern is exposed, introducing dopant and activating in the thin silicon layer to form doped regions. Then, bonding the silicon layer to an insulator substrate, and removing the silicon substrate. The method additionally involves forming electrical contact regions in the thin silicon layer for the buried collectors. 10 figs.

  15. Investigations on field optimization of insulator geometries

    SciTech Connect (OSTI)

    Daumling, H.H.; Singer, H.

    1989-01-01T23:59:59.000Z

    Today computer methods become more and more a useful help for the constructor of any high voltage components, because stresses on dielectric materials have become increasingly high. The paper describes new algorithms based on the CAD concept for optimizing insulator contours according to a given field distribution along their surfaces. These algorithms were applied to some examples of insulators. By means of experimental investigations it was found that it is not sufficient to achieve a low tangential field strength component but that it is necessary to reduce the maximum values of the total field strength as far as possible, especially in the case of high air humidities.

  16. Experience with 113 Retrofit Insulation Surveys

    E-Print Network [OSTI]

    Webber, W. O.

    EXPERIENCE WITH 113 RETROFIT INSULATION SURVEYS W. O. Webber Energy Conservation Consultants Baytown, Texas ABSTRACT We have surveyed 113 plants for thirteen clie~ts. The results of 21 recent surveys, at today s avera&e fuel price, show...,000 for $3.00 fuel up to $80,000 for $6.00 fuel. When this happens, the project return will increase from 100% up to 165% per year. The main problem that we have found with retrofit insulation surveys is the processing of detail in existing plants...

  17. Edge modes in band topological insulators

    E-Print Network [OSTI]

    Lukasz Fidkowski; T. S. Jackson; Israel Klich

    2011-05-09T23:59:59.000Z

    We characterize gapless edge modes in translation invariant topological insulators. We show that the edge mode spectrum is a continuous deformation of the spectrum of a certain gluing function defining the occupied state bundle over the Brillouin zone (BZ). Topologically non-trivial gluing functions, corresponding to non-trivial bundles, then yield edge modes exhibiting spectral flow. We illustrate our results for the case of chiral edge states in two dimensional Chern insulators, as well as helical edges in quantum spin Hall states.

  18. Rolling up SiGe on insulator

    SciTech Connect (OSTI)

    Cavallo, F.; Songmuang, R.; Ulrich, C.; Schmidt, O. G. [Max-Planck-Institut fuer Festkoerperforschung, Heisenbergstrasse 1, D-70569 Stuttgart (Germany)

    2007-05-07T23:59:59.000Z

    SiGe on insulator films of 10-50 nm thickness are fabricated by Ge condensation applying different oxidation times. The layers are released from the substrate by selectively etching the insulator film. Due to the varying Ge composition, the layers bend downward toward the substrate surface and roll up into microtubes. Depending on the Ge condensation, the strain distribution in the SiGe layers varies and allows a scaling of the tube diameters between 1 and 4 {mu}m. Assuming pseudomorphic SiGe layers, the tube diameters are smaller than expected from continuum mechanical theory. This suggests the occurrence of additional strain in the oxidized films.

  19. An analytical and experimental investigation for an interstitial insulation technology 

    E-Print Network [OSTI]

    Kim, Dong Keun

    2009-05-15T23:59:59.000Z

    An insulation technique has been developed which contains a single or combination of materials to help minimize heat loss in actual industrial applications. For the petroleum industry, insulation for deep sea piping is one of the greatest challenges...

  20. Insulated laser tube structure and method of making same

    DOE Patents [OSTI]

    Dittbenner, Gerald R. (4353 Findlay Way, Livermore, CA 94550)

    1999-01-01T23:59:59.000Z

    An insulated high temperature ceramic laser tube having substantially uniform insulation along the length of the tube is disclosed having particulate ceramic insulation positioned between the outer wall of the ceramic laser tube and the inner surface of tubular ceramic fiber insulation which surrounds the ceramic laser tube. The particulate ceramic insulation is preferably a ceramic capable of sintering to the outer surface of the ceramic laser tube and to the inner surface of the tubular ceramic fiber insulation. The addition of the particulate ceramic insulation to fill all the voids between the ceramic laser tube and the fibrous ceramic insulation permits the laser tube to be operated at a substantially uniform temperature throughout the length of the laser tube.

  1. Tuning of the Metal-Insulator Transition via Alkali Adsorption

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

    Tuning of the Metal-Insulator Transition via Alkali Adsorption Print Turning a material from an insulator to a metal, or vice versa, by light irradiation, exposure to electric or...

  2. Tuning of the Metal-Insulator Transition via Alkali Adsorption

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

    Tuning of the Metal-Insulator Transition via Alkali Adsorption Tuning of the Metal-Insulator Transition via Alkali Adsorption Print Wednesday, 29 March 2006 00:00 Turning a...

  3. Moisture Durability of Vapor Permeable Insulating Sheathing (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2013-10-01T23:59:59.000Z

    In this project, Building America team Building Science Corporation researched some of the ramifications of using exterior, vapor permeable insulation on retrofit walls with vapor permeable cavity insulation. Retrofit strategies are a key factor in reducing exterior building stock consumption.

  4. An analytical and experimental investigation for an interstitial insulation technology

    E-Print Network [OSTI]

    Kim, Dong Keun

    2009-05-15T23:59:59.000Z

    An insulation technique has been developed which contains a single or combination of materials to help minimize heat loss in actual industrial applications. For the petroleum industry, insulation for deep sea piping is one of the greatest challenges...

  5. Observation of a Macroscopically Quantum-Entangled Insulator

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

    Insulator Print Wednesday, 27 May 2009 00:00 It has recently been proposed that insulators with large band gaps and strong spin-orbit coupling can host a new phase of...

  6. Observation of a Macroscopically Quantum-Entangled Insulator

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

    of a Macroscopically Quantum-Entangled Insulator Print It has recently been proposed that insulators with large band gaps and strong spin-orbit coupling can host a new phase of...

  7. Gapped symmetry preserving surface state for the electron topological insulator

    E-Print Network [OSTI]

    Wang, Chong

    It is well known that the three-dimensional (3D) electronic topological insulator (TI) with charge-conservation and time-reversal symmetry cannot have a trivial insulating surface that preserves symmetry. It is often ...

  8. antisolar insulated roof: Topics by E-print Network

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

    A&M University - TxSpace Summary: PIPE INSULATION ECONOMIES Robert E. Schilling, P.E. Eaton Corporation Aurora, Ohio ABSTRACT Pipe Insulation Economies is a computer pro gram...

  9. airborne sound insulation: Topics by E-print Network

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

    A&M University - TxSpace Summary: PIPE INSULATION ECONOMIES Robert E. Schilling, P.E. Eaton Corporation Aurora, Ohio ABSTRACT Pipe Insulation Economies is a computer pro gram...

  10. affordable window insulation: Topics by E-print Network

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

    A&M University - TxSpace Summary: PIPE INSULATION ECONOMIES Robert E. Schilling, P.E. Eaton Corporation Aurora, Ohio ABSTRACT Pipe Insulation Economies is a computer pro gram...

  11. antiferromagnetic mott insulator: Topics by E-print Network

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

    A&M University - TxSpace Summary: PIPE INSULATION ECONOMIES Robert E. Schilling, P.E. Eaton Corporation Aurora, Ohio ABSTRACT Pipe Insulation Economies is a computer pro gram...

  12. atomic mott insulator: Topics by E-print Network

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

    A&M University - TxSpace Summary: PIPE INSULATION ECONOMIES Robert E. Schilling, P.E. Eaton Corporation Aurora, Ohio ABSTRACT Pipe Insulation Economies is a computer pro gram...

  13. alumina fibrous insulation: Topics by E-print Network

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

    A&M University - TxSpace Summary: PIPE INSULATION ECONOMIES Robert E. Schilling, P.E. Eaton Corporation Aurora, Ohio ABSTRACT Pipe Insulation Economies is a computer pro gram...

  14. Classification and characterization of topological insulators and superconductors

    E-Print Network [OSTI]

    Mong, Roger

    2012-01-01T23:59:59.000Z

    Weak topological insulators (WTI) . . . . . 1.4 Topologicalweak topological insulators (WTI). The surfaces of STIs haveSTI STM TI TRIM/TRIMs TRS TKNN VPT WTI one-dimension, two-

  15. Thermal protection apparatus

    DOE Patents [OSTI]

    Bennett, Gloria A. (Los Alamos, NM); Moore, Troy K. (Los Alamos, NM)

    1988-01-01T23:59:59.000Z

    An apparatus for thermally protecting heat sensitive components of tools. The apparatus comprises a Dewar for holding the heat sensitive components. The Dewar has spaced-apart inside and outside walls, an open top end and a bottom end. An insulating plug is located in the top end. The inside wall has portions defining an inside wall aperture located at the bottom of the Dewar and the outside wall has portions defining an outside wall aperture located at the bottom of the Dewar. A bottom connector has inside and outside components. The inside component sealably engages the inside wall aperture and the outside component sealably engages the outside wall aperture. The inside component is operatively connected to the heat sensitive components and to the outside component. The connections can be made with optical fibers or with electrically conducting wires.

  16. A study of the morphological and cytological changes in Century Patna 231 and Bluebonnet 50 rice varieties resulting from X-ray and thermal neutron radiation

    E-Print Network [OSTI]

    Hasanuzzaman, Shah Muhammad

    1959-01-01T23:59:59.000Z

    a PQ > I CQ *H -P 1 oas2 a O ? > ir\\ 1x1 oS E?*i U 0 1 S . N c o uYOf to C\\i vD O rH vO ?? c^ \\ 0^ o in m ?? COvflOn ? ? ? ?lA v?> t> "* CV O C V - J to H ( ^ O tO to% ? ? ? ? 0? 0 0 r H >4- C\\ v O C ^ v O........................................ 40 1 E. Century Patna 231 - Thermal Neutrons for 25 hours...................................4*5 DISCUSSION.............................................48 Meiotic disturbance in normal Century Patna 231....... 4*8 Types of chromosome pairing...

  17. Mechanics of Insulator Behavior in Concrete Crosstie Fastening Systems

    E-Print Network [OSTI]

    Barkan, Christopher P.L.

    of Insulator Behavior Analysis of failure modes and causes · Failure Mode and Effect Analysis (FMEA) used

  18. Molecular Cell Mode of Regulation and the Insulation

    E-Print Network [OSTI]

    Molecular Cell Article Mode of Regulation and the Insulation of Bacterial Gene Expression Vered.molcel.2012.04.032 SUMMARY A gene can be said to be insulated from environ- mental variations if its the insulation of the lac promoter of E. coli and of synthetic constructs in which the transcription factor CRP

  19. MOTT INSULATORS, SPIN LIQUIDS AND QUANTUM DISORDERED SUPERCONDUCTIVITY

    E-Print Network [OSTI]

    COURSE 7 MOTT INSULATORS, SPIN LIQUIDS AND QUANTUM DISORDERED SUPERCONDUCTIVITY MATTHEW P.A. FISHER insulators and quantum magnetism 583 3.1 Spin models and quantum magnetism . . . . . . . . . . . . . . . . . . . . . . . . . . . . 637 #12;MOTT INSULATORS, SPIN LIQUIDS AND QUANTUM DISORDERED SUPERCONDUCTIVITY Matthew P.A. Fisher

  20. Vacuum insulation tandem accelerator for B. Bayanov1

    E-Print Network [OSTI]

    Taskaev, Sergey Yur'evich

    273 Vacuum insulation tandem accelerator for NCT B. Bayanov1 , Yu. Belchenko1 , V. Belov1 , G of high current hydrogen negative ions by special geometry of potential electrodes with vacuum insulation. Fig. 1 shows the construction of vacuum insulation tandem accelerator developed at BINP, as a base

  1. Topological insulators and superconductors Xiao-Liang Qi

    E-Print Network [OSTI]

    Wu, Zhigang

    Topological insulators and superconductors Xiao-Liang Qi Microsoft Research, Station Q, Elings Hall, California 94305, USA (Received 2 August 2010; published 14 October 2011) Topological insulators are new-dimensional and three-dimensional topological insulators are reviewed, and both the topological band theory

  2. Updated evaluation of polymer films for electrical insulation

    SciTech Connect (OSTI)

    McCoy, H.E. Jr.

    1990-08-01T23:59:59.000Z

    Several types of tests have been run on polymer film materials that could be useful for electrical insulation. The polymers studied were polyethylene terephtalate, polycarbonate, polysulfone, polyetherimide, ultrahigh-molecular-weight polyethylene, polyimide, polybutylene terephthalate, and a laminate of Kraft paper and polypropylene. Thermal aging tests were run to 60,000 h on several of the polymers, and the samples were evaluated by tensile tests, electrical breakdown tests, and immersion density measurements. Because of the wide range of potential service conditions, tensile tests were run on as-received materials over the temperature range of {minus}196 to 200{degree}C. Polyimide is probably the only material suitable for the extremes of this temperature range, but many of the other polymers would be suitable for intermediate temperatures. Creep tests were run in nitrogen and transformer oil at 90{degree}C. It was found that some polymers are weaker and less ductile in oil than in nitrogen and that other polymers have equivalent properties in the two environments. A means of applying mechanical, thermal, and electrical stresses simultaneously to polymer samples was developed. Tests were run at 90{degree}C in transformer oil on polyethylene terephthalate, polyimide, and polyethersulfone. Tests thus far do not indicate that the creep rate is affected by the application of a 5 kV dc potential. 7 refs., 30 figs., 16 tabs.

  3. The Insulation Energy Appraisal Assessing the True Value of Insulated System

    E-Print Network [OSTI]

    Schell, S.

    Insulation remains a seriously under-utilized technology in the manufacturing and industrial sectors of the economy even though its role in energy efficiency and environmental preservation is clear. The objective of the presentation is to educate...

  4. ASBESTOS PIPE-INSULATION REMOVAL ROBOT SYSTEM

    SciTech Connect (OSTI)

    Unknown

    2000-09-15T23:59:59.000Z

    This final topical report details the development, experimentation and field-testing activities for a robotic asbestos pipe-insulation removal robot system developed for use within the DOE's weapon complex as part of their ER and WM program, as well as in industrial abatement. The engineering development, regulatory compliance, cost-benefit and field-trial experiences gathered through this program are summarized.

  5. Tunable Chern insulator with shaken optical lattices

    E-Print Network [OSTI]

    Albert Verdeny; Florian Mintert

    2015-04-16T23:59:59.000Z

    Driven optical lattices permit the engineering of effective dynamics with well-controllable tunneling properties. We describe the realization of a tunable a Chern insulator by driving particles on a shaken hexagonal lattice with optimally designed polychromatic driving forces. Its implementation does not require shallow lattices, which favors the study of strongly-correlated phases with non-trivial topology.

  6. TRANSITION DE MOTT METAL-INSULATOR TRANSITIONS

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    TRANSITION DE MOTT METAL-INSULATOR TRANSITIONS IN TRANSITION METAL OXIDES by D. B. McWHAN, A. MENTH oxydes de metaux de transition on observe une transition d'isolant a metal puis de metal a isolant de type Mott lorsque l'on augmentelenombre d'electrons d. Danslesysthe(V1-~Cr~)203une transition de Mott

  7. D-Algebra Structure of Topological Insulators

    E-Print Network [OSTI]

    B. Estienne; N. Regnault; B. A. Bernevig

    2013-02-01T23:59:59.000Z

    In the quantum Hall effect, the density operators at different wave-vectors generally do not commute and give rise to the Girvin MacDonald Plazmann (GMP) algebra with important consequences such as ground-state center of mass degeneracy at fractional filling fraction, and W_{1 + \\infty} symmetry of the filled Landau levels. We show that the natural generalization of the GMP algebra to higher dimensional topological insulators involves the concept of a D-algebra formed by using the fully anti-symmetric tensor in D-dimensions. For insulators in even dimensional space, the D-algebra is isotropic and closes for the case of constant non-Abelian F(k) ^ F(k) ... ^ F(k) connection (D-Berry curvature), and its structure factors are proportional to the D/2-Chern number. In odd dimensions, the algebra is not isotropic, contains the weak topological insulator index (layers of the topological insulator in one less dimension) and does not contain the Chern-Simons \\theta form (F ^ A - 2/3 A ^ A ^ A in 3 dimensions). The Chern-Simons form appears in a certain combination of the parallel transport and simple translation operator which is not an algebra. The possible relation to D-dimensional volume preserving diffeomorphisms and parallel transport of extended objects is also discussed.

  8. Tubing carried perforating gun with insulation jacket

    SciTech Connect (OSTI)

    Donovan, J.F.; Yates, D.N.

    1991-05-21T23:59:59.000Z

    This patent describes a method of insulating a tubing carried perforating gun which is run through a subterranean wellbore. It includes making up at the well surface a tubing string for introduction within the well, the tubing string carrying a perforating gun assembly.

  9. BOA: Asbestos pipe-insulation removal robot system, Phase 2. Topical report, January--June 1995

    SciTech Connect (OSTI)

    Schempf, H.; Bares, J.E.

    1995-06-01T23:59:59.000Z

    This report explored the regulatory impact and cost-benefit of a robotic thermal asbestos pipe-insulation removal system over the current manual abatement work practice. The authors are currently in the second phase of a two-phase program to develop a robotic asbestos abatement system, comprised of a ground-based support system (including vacuum, fluid delivery, computing/electronics/power, and other subsystems) and several on-pipe removal units, each sized to handle pipes within a given diameter range. The intent of this study was to (i) aid in developing design and operational criteria for the overall system to maximize cost-efficiency, and (ii) to determine the commercial potential of a robotic pipe-insulation abatement system.

  10. Modeling PCM-Enhanced Insulation System and Benchmarking EnergyPlus against Controlled Field Data

    SciTech Connect (OSTI)

    Shrestha, Som S [ORNL] [ORNL; Miller, William A [ORNL] [ORNL; Stovall, Therese K [ORNL] [ORNL; Desjarlais, Andre Omer [ORNL] [ORNL; Childs, Kenneth W [ORNL] [ORNL; Porter, Wallace D [ORNL] [ORNL; Bhandari, Mahabir S [ORNL] [ORNL; Coley, Steven J [ORNL] [ORNL

    2011-01-01T23:59:59.000Z

    Phase-change materials (PCM) used in building envelopes appear to be a promising technology to reduce energy consumption and reduce/shift peak load. However, due to complexity in modeling the dynamic behavior of PCMs, current modeling tools either lack an accurate way of predicting the performance and impact of PCMs in buildings or validation of predicted or measured performance is not available. This paper presents a model of a PCM-enhanced dynamic-insulation system in EnergyPlus (E+) and compares the simulation results against field-measured data. Laboratory tests to evaluate thermal properties and to characterize the PCM and PCM-enhanced cellulose insulation system are also presented in this paper. Results indicate that the predicted daily average heat flux through walls from the E+ simulation was within 9% of field measured data. Future analysis will allow us to predict annual energy savings from the use of PCM in buildings.

  11. Highly Insulating Glazing Systems using Non-Structural Center Glazing Layers

    SciTech Connect (OSTI)

    Kohler, Christian; Arasteh, Dariush; Goudey, Howdy; Kohler, Christian

    2008-04-09T23:59:59.000Z

    Three layer insulating glass units with two low-e coatings and an effective gas fill are known to be highly insulating, with center-of-glass U-factors as low as 0.57 W/m{sup 2}-K (0.10 Btu/h-ft{sup 2}- F). Such units have historically been built with center layers of glass or plastic which extend all the way through the spacer system. This paper shows that triple glazing systems with non-structural center layers which do not create a hermetic seal at the edge have the potential to be as thermally efficient as standard designs, while potentially removing some of the production and product integration issues that have discouraged the use of triples.

  12. Hygric Redistribution in Insulated Assemblies: Retrofitting Residential Envelopes Without Creating Moisture Issues

    SciTech Connect (OSTI)

    Smegal, J.; Lstiburek, J.

    2013-01-01T23:59:59.000Z

    The Building America program has recognized that most of the current housing stock is in need of energy related retrofits. One of the best ways of reducing the space conditioning energy consumption is to improve the thermal performance of the enclosure by adding exterior board foam insulation. This report quantifies the amount of water that can become trapped in the drainage cavity of typical wall systems, and measures the effect of water trapped in the drainage cavity on the moisture content of the sheathing. This study also attempts to explain the discrepancy between hygrothermal simulations and field performance of low permeance, low R-value exterior insulation (e.g. 3/4-in. foil faced polyisocyanurate) in cold climates.

  13. Vacuum Insulator Development for the Dielectric Wall Accelerator

    SciTech Connect (OSTI)

    Harris, J R; Blackfield, D; Caporaso, G J; Chen, Y; Hawkins, S; Kendig, M; Poole, B; Sanders, D M; Krogh, M; Managan, J E

    2008-03-17T23:59:59.000Z

    At Lawrence Livermore National Laboratory, we are developing a new type of accelerator, known as a Dielectric Wall Accelerator, in which compact pulse forming lines directly apply an accelerating field to the beam through an insulating vacuum boundary. The electrical strength of this insulator may define the maximum gradient achievable in these machines. To increase the system gradient, we are using 'High Gradient Insulators' composed of alternating layers of dielectric and metal for the vacuum insulator. In this paper, we present our recent results from experiment and simulation, including the first test of a High Gradient Insulator in a functioning Dielectric Wall Accelerator cell.

  14. Four cavity efficiency enhanced magnetically insulated line oscillator

    DOE Patents [OSTI]

    Lemke, R.W.; Clark, M.C.; Calico, S.E.

    1998-04-21T23:59:59.000Z

    A four cavity, efficient magnetically insulated line oscillator (C4-E MILO) having seven vanes and six cavities formed within a tube-like structure surrounding a cathode is disclosed. The C4-E MILO has a primary slow wave structure which is comprised of four vanes and the four cavities located near a microwave exit end of the tube-like structure. The primary slow wave structure is the four cavity portion of the magnetically insulated line oscillator (MILO). An RF choke is provided which is comprised of three of the vanes and two of the cavities. The RF choke is located near a pulsed power source portion of the tube-like structure surrounding the cathode. The RF choke increases feedback in the primary slow wave structure, prevents microwaves generated in the primary slow wave structure from propagating towards the pulsed power source and modifies downstream electron current so as to enhance microwave power generation. A beam dump/extractor is located at the exit end of the oscillator tube for extracting microwave power from the oscillator, and in conjunction with an RF extractor vane, which comprises the fourth vane of the primary slow wave structure (nearest the exit) having a larger gap radius than the other vanes of the primary SWS, comprises an RF extractor. Uninsulated electron flow is returned downstream towards the exit along an anode/beam dump region located between the beam dump/extractor and the exit where the RF is radiated at said RF extractor vane located near the exit and the uninsulated electron flow is disposed at the beam dump/extractor. 34 figs.

  15. Four cavity efficiency enhanced magnetically insulated line oscillator

    DOE Patents [OSTI]

    Lemke, Raymond W. (Albuquerque, NM); Clark, Miles C. (Albuquerque, NM); Calico, Steve E. (Albuquerque, NM)

    1998-04-21T23:59:59.000Z

    A four cavity, efficient magnetically insulated line oscillator (C4-E MILO) having seven vanes and six cavities formed within a tube-like structure surrounding a cathode. The C4-E MILO has a primary slow wave structure which is comprised of four vanes and the four cavities located near a microwave exit end of the tube-like structure. The primary slow wave structure is the four cavity (C4) portion of the magnetically insulated line oscillator (MILO). An RF choke is provided which is comprised of three of the vanes and two of the cavities. The RF choke is located near a pulsed power source portion of the tube-like structure surrounding the cathode. The RF choke increases feedback in the primary slow wave structure, prevents microwaves generated in the primary slow wave structure from propagating towards the pulsed power source and modifies downstream electron current so as to enhance microwave power generation. A beam dump/extractor is located at the exit end of the oscillator tube for extracting microwave power from the oscillator, and in conjunction with an RF extractor vane, which comprises the fourth vane of the primary slow wave structure (nearest the exit) having a larger gap radius than the other vanes of the primary SWS, comprises an RF extractor. Uninsulated electron flow is returned downstream towards the exit along an anode/beam dump region located between the beam dump/extractor and the exit where the RF is radiated at said RF extractor vane located near the exit and the uninsulated electron flow is disposed at the beam dump/extractor.

  16. Side-by-Side Field Evaluation of Highly Insulating Windows in the PNNL Lab Homes

    SciTech Connect (OSTI)

    Widder, Sarah H.; Parker, Graham B.; Baechler, Michael C.; Bauman, Nathan N.

    2012-08-01T23:59:59.000Z

    To examine the energy, air leakage, and thermal performance of highly insulating windows, a field evaluation was undertaken in a matched pair of all-electric, factory-built “Lab Homes” located on the Pacific Northwest National Laboratory (PNNL) campus in Richland, Washington. The “baseline” Lab Home B was retrofitted with “standard” double-pane clear aluminum-frame slider windows and patio doors, while the “experimental” Lab Home A was retrofitted with Jeld-Wen® triple-pane vinyl-frame slider windows and patio doors with a U-factor of 0.2 and solar heat gain coefficient of 0.19. To assess the window, the building shell air leakage, energy use, and interior temperatures of each home were compared during the 2012 winter heating and summer cooling seasons. The measured energy savings in Lab Home B averaged 5,821 watt-hours per day (Wh/day) during the heating season and 6,518 Wh/day during the cooling season. The overall whole-house energy savings of Lab Home B compared to Lab Home A are 11.6% ± 1.53% for the heating season and 18.4 ± 2.06% for the cooling season for identical occupancy conditions with no window coverings deployed. Extrapolating these energy savings numbers based on typical average heating degree days and cooling degree days per year yields an estimated annual energy savings of 12.2%, or 1,784 kWh/yr. The data suggest that highly insulating windows are an effective energy-saving measure that should be considered for high-performance new homes and in existing retrofits. However, the cost effectiveness of the measure, as determined by the simple payback period, suggests that highly insulating window costs continue to make windows difficult to justify on a cost basis alone. Additional reductions in costs via improvements in manufacturing and/or market penetration that continue to drive down costs will make highly insulating windows much more viable as a cost-effective energy efficiency measure. This study also illustrates that highly insulating windows have important impacts on peak load, occupant comfort, and condensation potential, which are not captured in the energy savings calculation. More consistent and uniform interior temperature distributions suggest that highly insulated windows, as part of a high performance building envelope, may enable more centralized duct design and downsized HVAC systems. Shorter, more centralized duct systems and smaller HVAC systems to yield additional cost savings, making highly insulating windows more cost effective as part of a package of new construction or retrofit measures which achieve significant reductions in home energy use.

  17. Solar energy thermalization and storage device

    DOE Patents [OSTI]

    McClelland, John F. (Ames, IA)

    1981-09-01T23:59:59.000Z

    A passive solar thermalization and thermal energy storage assembly which is visually transparent. The assembly consists of two substantial parallel, transparent wall members mounted in a rectangular support frame to form a liquid-tight chamber. A semitransparent thermalization plate is located in the chamber, substantially paralled to and about equidistant from the transparent wall members to thermalize solar radiation which is stored in a transparent thermal energy storage liquid which fills the chamber. A number of the devices, as modules, can be stacked together to construct a visually transparent, thermal storage wall for passive solar-heated buildings.

  18. Radiation dosimeters

    DOE Patents [OSTI]

    Hoelsher, James W. (Pullman, WA); Hegland, Joel E. (Pullman, WA); Braunlich, Peter F. (Pullman, WA); Tetzlaff, Wolfgang (Pullman, WA)

    1992-01-01T23:59:59.000Z

    Radiation dosimeters and dosimeter badges. The dosimeter badges include first and second parts which are connected to join using a securement to produce a sealed area in which at least one dosimeter is held and protected. The badge parts are separated to expose the dosimeters to a stimulating laser beam used to read dose exposure information therefrom. The badge is constructed to allow automated disassembly and reassembly in a uniquely fitting relationship. An electronic memory is included to provide calibration and identification information used during reading of the dosimeter. Dosimeter mounts which reduce thermal heating requirements are shown. Dosimeter constructions and production methods using thin substrates and phosphor binder-layers applied thereto are also taught.

  19. Radiation Modeling In Fluid Flow Iain D. Boyd

    E-Print Network [OSTI]

    Wang, Wei

    Collector #12;4 Fundamentals of Radiation (1) · All matter with non-zero temperature emits thermal radiation with energy flux given by the Stefan-Boltzmann Law: e.g., Sun: T=5800 K, total radiated power = 4 distribution (Planck spectrum) !q =T 4 W/m2 #12;5 Planck Radiation Spectrum #12;6 Solar Radiation Spectrum

  20. MAGNETOHYDRODYNAMIC AND THERMAL ISSUES OF THE SiCf0SiC FLOW CHANNEL INSERT

    E-Print Network [OSTI]

    Abdou, Mohamed

    ) made of a silicon carbide composite (SiCf /SiC), which serves as electric and thermal insulator considered. The computa- tions were performed in a parametric form, using the electric and thermal. INTRODUCTION Flow channel inserts ~FCIs! made of a silicon car- bide composite ~SiCf 0SiC! were first proposed

  1. Local microwave background radiation

    E-Print Network [OSTI]

    Domingos Soares

    2014-11-13T23:59:59.000Z

    An inquiry on a possible local origin for the Microwave Background Radiation is made. Thermal MBR photons are contained in a system called {\\it magnetic bottle} which is due to Earth magnetic field and solar wind particles, mostly electrons. Observational tests are anticipated.

  2. Three Dimensional Radiative Transfer

    E-Print Network [OSTI]

    Tom Abel

    2000-05-09T23:59:59.000Z

    Radiative Transfer (RT) effects play a crucial role in the thermal history of the intergalactic medium. Here I discuss recent advances in the development of numerical methods that introduce RT to cosmological hydrodynamics. These methods can also readily be applied to time dependent problems on interstellar and galactic scales.

  3. Contaminant trap for gas-insulated apparatus

    DOE Patents [OSTI]

    Adcock, James L. (Knoxville, TN); Pace, Marshall O. (Knoxville, TN); Christophorou, Loucas G. (Oak Ridge, TN)

    1984-01-01T23:59:59.000Z

    A contaminant trap for a gas-insulated electrical conductor is provided. A resinous dielectric body such as Kel-F wax, grease or other sticky polymeric or oligomeric compound is disposed on the inside wall of the outer housing for the conductor. The resinous body is sufficiently sticky at ambient temperatures to immobilize contaminant particles in the insulating gas on the exposed surfaces thereof. An electric resistance heating element is disposed in the resinous body to selectively raise the temperature of the resinous body to a molten state so that the contaminant particles collected on the surface of the body sink into the body so that the surface of the resinous body is renewed to a particle-less condition and, when cooled, returns to a sticky collecting surface.

  4. Multiterminal Conductance of a Floquet Topological Insulator

    E-Print Network [OSTI]

    L. E. F. Foa Torres; P. M. Perez-Piskunow; C. A. Balseiro; G. Usaj

    2014-09-08T23:59:59.000Z

    We report on simulations of the dc conductance and quantum Hall response of a Floquet topological insulator using Floquet scattering theory. Our results reveal that laser-induced edge states in graphene lead to quantum Hall plateaus once imperfect matching with the non-illuminated leads is lessened. But the magnitude of the Hall plateaus is not directly related to the number and chirality of all the edge states at a given energy as usual. Instead, the plateaus are dominated only by those edge states adding to the dc density of states. Therefore, the dc quantum Hall conductance of a Floquet topological insulator is not directly linked to topological invariants of the full the Floquet bands.

  5. Electric-Magnetic Duality and Topological Insulators

    E-Print Network [OSTI]

    Andreas Karch

    2009-10-03T23:59:59.000Z

    We work out the action of the SL(2,Z) electric-magnetic duality group for an insulator with a non-trivial permittivity, permeability and theta-angle. This theory has recently been proposed to be the correct low-energy effective action for topological insulators. As applications, we give manifestly SL(2,Z) covariant expressions for the Faraday rotation at orthogonal incidence at the interface of two such materials, as well as for the induced magnetic and electric charges, slightly clarifying the meaning of expressions previously derived in the literature. We also use electric-magnetic duality to find a gravitational dual for a strongly coupled version of this theory using the AdS/CFT correspondence.

  6. Fractional topological insulators in three dimensions

    E-Print Network [OSTI]

    Joseph Maciejko; Xiao-Liang Qi; Andreas Karch; Shou-Cheng Zhang

    2010-11-14T23:59:59.000Z

    Topological insulators can be generally defined by a topological field theory with an axion angle theta of 0 or pi. In this work, we introduce the concept of fractional topological insulator defined by a fractional axion angle and show that it can be consistent with time reversal (T) invariance if ground state degeneracies are present. The fractional axion angle can be measured experimentally by the quantized fractional bulk magnetoelectric polarization P_3, and a `halved' fractional quantum Hall effect on the surface with Hall conductance of the form (p/q)(e^2/2h) with p,q odd. In the simplest of these states the electron behaves as a bound state of three fractionally charged `quarks' coupled to a deconfined non-Abelian SU(3) `color' gauge field, where the fractional charge of the quarks changes the quantization condition of P_3 and allows fractional values consistent with T-invariance.

  7. Electric-Magnetic Duality and Topological Insulators

    SciTech Connect (OSTI)

    Karch, A. [Department of Physics, University of Washington, Seattle, Washington 98195-1560 (United States)

    2009-10-23T23:59:59.000Z

    We work out the action of the SL(2,Z) electric-magnetic duality group for an insulator with a nontrivial permittivity, permeability, and theta angle. This theory has recently been proposed to be the correct low-energy effective action for topological insulators. As applications, we give manifestly SL(2,Z) covariant expressions for the Faraday rotation at orthogonal incidence at the interface of two such materials, as well as for the induced magnetic and electric charges, slightly clarifying the meaning of expressions previously derived in the literature. We also use electric-magnetic duality to find a gravitational dual for a strongly coupled version of this theory using the gauge/gravity correspondence.

  8. Fractional Topological Insulators in Three Dimensions

    SciTech Connect (OSTI)

    Maciejko, Joseph; Zhang Shoucheng [Department of Physics, Stanford University, Stanford, California 94305 (United States); Qi Xiaoliang [Microsoft Research, Station Q, Elings Hall, University of California, Santa Barbara, California 93106 (United States); Department of Physics, Stanford University, Stanford, California 94305 (United States); Karch, Andreas [Department of Physics, University of Washington, Seattle, Washington 98195-1560 (United States)

    2010-12-10T23:59:59.000Z

    Topological insulators can be generally defined by a topological field theory with an axion angle {theta} of 0 or {pi}. In this work, we introduce the concept of fractional topological insulator defined by a fractional axion angle and show that it can be consistent with time reversal T invariance if ground state degeneracies are present. The fractional axion angle can be measured experimentally by the quantized fractional bulk magnetoelectric polarization P{sub 3}, and a 'halved' fractional quantum Hall effect on the surface with Hall conductance of the form {sigma}{sub H}=(p/q)(e{sup 2}/2h) with p, q odd. In the simplest of these states the electron behaves as a bound state of three fractionally charged 'quarks' coupled to a deconfined non-Abelian SU(3) 'color' gauge field, where the fractional charge of the quarks changes the quantization condition of P{sub 3} and allows fractional values consistent with T invariance.

  9. Transgression field theory for interacting topological insulators

    E-Print Network [OSTI]

    Aç?k, Özgür

    2013-01-01T23:59:59.000Z

    We consider effective topological field theories of quantum Hall systems and time-reversal invariant topological insulators that are Chern-Simons and BF field theories. The edge states of these systems are related to the gauge invariance of the effective actions. For the edge states at the interface of two topological insulators, transgression field theory is proposed as a gauge invariant effective action. Transgression actions of Chern-Simons theories for (2+1)D and (4+1)D and BF theories for (3+1)D are constructed. By using transgression actions, the edge states are written in terms of the bulk connections of effective Chern-Simons and BF theories.

  10. High temperature insulation for ceramic matrix composites

    SciTech Connect (OSTI)

    Merrill, Gary B. (Monroeville, PA); Morrison, Jay Alan (Orlando, FL)

    2000-01-01T23:59:59.000Z

    A ceramic composition is provided to insulate ceramic matrix composites under high temperature, high heat flux environments. The composite comprises a plurality of hollow oxide-based spheres of varios dimentions, a phosphate binder, and at least one oxide filler powder, whereby the phosphate binder partially fills gaps between the spheres and the filler powders. The spheres are situated in the phosphate binder and the filler powders such that each sphere is in contact with at least one other sphere. The spheres may be any combination of Mullite spheres, Alumina spheres, or stabilized Zirconia spheres. The filler powder may be any combination of Alumina, Mullite, Ceria, or Hafnia. Preferably, the phosphate binder is Aluminum Ortho-Phosphate. A method of manufacturing the ceramic insulating composition and its application to CMC substates are also provided.

  11. High temperature insulation for ceramic matrix composites

    DOE Patents [OSTI]

    Merrill, Gary B.; Morrison, Jay Alan

    2004-01-13T23:59:59.000Z

    A ceramic composition is provided to insulate ceramic matrix composites under high temperature, high heat flux environments. The composition comprises a plurality of hollow oxide-based spheres of various dimensions, a phosphate binder, and at least one oxide filler powder, whereby the phosphate binder partially fills gaps between the spheres and the filler powders. The spheres are situated in the phosphate binder and the filler powders such that each sphere is in contact with at least one other sphere. The spheres may be any combination of Mullite spheres, Alumina spheres, or stabilized Zirconia spheres. The filler powder may be any combination of Alumina, Mullite, Ceria, or Hafnia. Preferably, the phosphate binder is Aluminum Ortho-Phosphate. A method of manufacturing the ceramic insulating composition and its application to CMC substrates are also provided.

  12. High temperature insulation for ceramic matrix composites

    SciTech Connect (OSTI)

    Merrill, Gary B. (Monroeville, PA); Morrison, Jay Alan (Orlando, FL)

    2001-01-01T23:59:59.000Z

    A ceramic composition is provided to insulate ceramic matrix composites under high temperature, high heat flux environments. The composition comprises a plurality of hollow oxide-based spheres of various dimensions, a phosphate binder, and at least one oxide filler powder, whereby the phosphate binder partially fills gaps between the spheres and the filler powders. The spheres are situated in the phosphate binder and the filler powders such that each sphere is in contact with at least one other sphere. The spheres may be any combination of Mullite spheres, Alumina spheres, or stabilized Zirconia spheres. The filler powder may be any combination of Alumina, Mullite, Ceria, or Hafnia. Preferably, the phosphate binder is Aluminum Ortho-Phosphate. A method of manufacturing the ceramic insulating composition and its application to CMC substrates are also provided.

  13. The topological insulator in a fractal space

    SciTech Connect (OSTI)

    Song, Zhi-Gang; Zhang, Yan-Yang; Li, Shu-Shen [SKLSM, Institute of Semiconductors, Chinese Academy of Sciences, P.O. Box 912, Beijing 100083 (China)

    2014-06-09T23:59:59.000Z

    We investigate the band structures and transport properties of a two-dimensional model of topological insulator, with a fractal edge or a fractal bulk. A fractal edge does not affect the robust transport even when the fractal pattern has reached the resolution of the atomic-scale, because the bulk is still well insulating against backscattering. On the other hand, a fractal bulk can support the robust transport only when the fractal resolution is much larger than a critical size. Smaller resolution of bulk fractal pattern will lead to remarkable backscattering and localization, due to strong couplings of opposite edge states on narrow sub-edges which appear almost everywhere in the fractal bulk.

  14. Thermal axion constraints in non-standard thermal histories

    SciTech Connect (OSTI)

    Grin, Daniel; Smith, Tristan; Kamionkowski, Marc [California Institute of Technology, Mail Code 130-33, Pasadena, CA 91125 (United States)

    2010-08-30T23:59:59.000Z

    There is no direct evidence for radiation domination prior to big-bang nucleosynthesis, and so it is useful to consider how constraints to thermally-produced axions change in non-standard thermal histories. In the low-temperature-reheating scenario, radiation domination begins as late as {approx}1 MeV, and is preceded by significant entropy generation. Axion abundances are then suppressed, and cosmological limits to axions are significantly loosened. In a kination scenario, a more modest change to axion constraints occurs. Future possible constraints to axions and low-temperature reheating are discussed.

  15. Thermal axion constraints in non-standard thermal histories

    E-Print Network [OSTI]

    Daniel Grin; Tristan Smith; Marc Kamionkowski

    2009-11-10T23:59:59.000Z

    There is no direct evidence for radiation domination prior to big-bang nucleosynthesis, and so it is useful to consider how constraints to thermally-produced axions change in non-standard thermal histories. In the low-temperature-reheating scenario, radiation domination begins at temperatures as low as 1 MeV, and is preceded by significant entropy generation. Axion abundances are then suppressed, and cosmological limits to axions are significantly loosened. In a kination scenario, a more modest change to axion constraints occurs. Future possible constraints to axions and low-temperature reheating are discussed.

  16. Three-Dimensional Thermal Tomography Advances Cancer Treatment...

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

    Three-Dimensional Thermal Tomography Advances Cancer Treatment Technology available for licensing: A 3D technique to detect early skin changes due to radiation treatment in breast...

  17. Development of high performance refractory fibers with enhanced insulating properties and longer service lifetimes

    SciTech Connect (OSTI)

    Martin, P.C.; DePoorter, G.L.; Munoz, D.R.

    1991-02-01T23:59:59.000Z

    We have initiated a three phase investigation of the development of high performance refractory fibers with enhanced insulating properties and longer usable lifetimes. This report presents the results of the first phase of the study, performed from Aug. 1989 through Feb. 1991, which shows that significant energy saving are possible through the use of high temperature insulating fibers that better retain their efficient insulating properties during the service lifetime of the fibers. The remaining phases of this program include the pilot scale development and then full scale production feasibility development and evaluation of enhanced high temperature refractory insulting fibers. This first proof of principle phase of the program presents a summary of the current use patterns of refractory fibers, a laboratory evaluation of the high temperature performance characteristics of selected typical refractory fibers and an analysis of the potential energy savings through the use of enhanced refractory fibers. The current use patterns of refractory fibers span a wide range of industries and high temperature furnaces within those industries. The majority of high temperature fiber applications are in furnaces operating between 2000 and 26000{degrees}F. The fibers used in furnaces operating within this range provide attractive thermal resistance and low thermal storage at reasonable cost. A series of heat treatment studies performed for this phase of the program has shown that the refractory fibers, as initially manufactured, have attractive thermal conductivities for high temperature applications but the fibers go through rapid devitrification and subsequent crystal growth upon high temperature exposure. Development of improved fibers, maintaining the favorable characteristics of the existing as-manufactured fibers, could save between 1 and 4% of the energy consumed in high temperature furnaces using refractory fibers.

  18. Excavationless Exterior Foundation Insulation Exploratory Study

    SciTech Connect (OSTI)

    Mosiman, G.; Wagner, R.; Schirber, T.

    2013-02-01T23:59:59.000Z

    The key objective of this exploratory study was to investigate the feasibility of the development or adoption of technologies that would enable a large percentage of existing homes in cold climates to apply a combination 'excavationless' soil removal process with appropriate insulation and water management on the exterior of existing foundations at a low cost. Our approach was to explore existing excavation and material technologies and systems to discover whether potential successful combinations existed.

  19. Thermal and non-thermal energies in solar flares

    E-Print Network [OSTI]

    Pascal Saint-Hilaire; Arnold O. Benz

    2005-03-03T23:59:59.000Z

    The energy of the thermal flare plasma and the kinetic energy of the non-thermal electrons in 14 hard X-ray peaks from 9 medium-sized solar flares have been determined from RHESSI observations. The emissions have been carefully separated in the spectrum. The turnover or cutoff in the low-energy distribution of electrons has been studied by simulation and fitting, yielding a reliable lower limit to the non-thermal energy. It remains the largest contribution to the error budget. Other effects, such as albedo, non-uniform target ionization, hot target, and cross-sections on the spectrum have been studied. The errors of the thermal energy are about equally as large. They are due to the estimate of the flare volume, the assumption of the filling factor, and energy losses. Within a flare, the non-thermal/thermal ratio increases with accumulation time, as expected from loss of thermal energy due to radiative cooling or heat conduction. Our analysis suggests that the thermal and non-thermal energies are of the same magnitude. This surprising result may be interpreted by an efficient conversion of non-thermal energy to hot flare plasma.

  20. Humidity effects on wire insulation breakdown strength.

    SciTech Connect (OSTI)

    Appelhans, Leah

    2013-08-01T23:59:59.000Z

    Methods for the testing of the dielectric breakdown strength of insulation on metal wires under variable humidity conditions were developed. Two methods, an ASTM method and the twisted pair method, were compared to determine if the twisted pair method could be used for determination of breakdown strength under variable humidity conditions. It was concluded that, although there were small differences in outcomes between the two testing methods, the non-standard method (twisted pair) would be appropriate to use for further testing of the effects of humidity on breakdown performance. The dielectric breakdown strength of 34G copper wire insulated with double layer Poly-Thermaleze/Polyamide-imide insulation was measured using the twisted pair method under a variety of relative humidity (RH) conditions and exposure times. Humidity at 50% RH and below was not found to affect the dielectric breakdown strength. At 80% RH the dielectric breakdown strength was significantly diminished. No effect for exposure time up to 140 hours was observed at 50 or 80%RH.

  1. Witten effect in a crystalline topological insulator

    SciTech Connect (OSTI)

    Rosenberg, G.; Franz, M. [Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia, V6T 1Z1 (Canada)

    2010-07-15T23:59:59.000Z

    It has been noted a long time ago that a term of the form theta(e{sup 2}/2pih)Bcentre dotE may be added to the standard Maxwell Lagrangian without modifying the familiar laws of electricity and magnetism. theta is known to particle physicists as the 'axion' field and whether or not it has a nonzero expectation value in vacuum remains a fundamental open question of the standard model. A key manifestation of the axion term is the Witten effect: a unit magnetic monopole placed inside a medium with thetanot =0 is predicted to bind a (generally fractional) electric charge -e(theta/2pi+n) with n integer. Here we conduct a test of the Witten effect based on the recently established fact that the axion term with theta=pi emerges naturally in the description of the electromagnetic response of a class of crystalline solids called topological insulators--materials distinguished by strong spin-orbit coupling and nontrivial band structures. Using a simple physical model for a topological insulator we demonstrate the existence of a fractional charge bound to a monopole by an explicit numerical calculation. We also propose a scheme for generating an 'artificial' magnetic monopole in a topological insulator film that may be used to facilitate an experimental test of Witten's prediction.

  2. Topological insulators with arbitrarily tunable entanglement

    E-Print Network [OSTI]

    J. C. Budich; J. Eisert; E. J. Bergholtz

    2014-05-15T23:59:59.000Z

    We elucidate how Chern and topological insulators fulfill an area law for the entanglement entropy. By explicit construction of a family of lattice Hamiltonians, we are able to demonstrate that the area law contribution can be tuned to an arbitrarily small value, but is topologically protected from vanishing exactly. We prove this by introducing novel methods to bound entanglement entropies from correlations using perturbation bounds, drawing intuition from ideas of quantum information theory. This rigorous approach is complemented by an intuitive understanding in terms of entanglement edge states. These insights have a number of important consequences: The area law has no universal component, no matter how small, and the entanglement scaling cannot be used as a faithful diagnostic of topological insulators. This holds for all Renyi entropies which uniquely determine the entanglement spectrum which is hence also non-universal. The existence of arbitrarily weakly entangled topological insulators furthermore opens up possibilities of devising correlated topological phases in which the entanglement entropy is small and which are thereby numerically tractable, specifically in tensor network approaches.

  3. Passive-solar directional-radiating cooling system

    DOE Patents [OSTI]

    Hull, J.R.; Schertz, W.W.

    1985-06-27T23:59:59.000Z

    A radiative cooling system for use with an ice-making system having a radiating surface aimed at the sky for radiating energy at one or more wavelength bands for which the atmosphere is transparent and a cover thermally isolated from the radiating surface and transparent at least to the selected wavelength or wavelengths, the thermal isolation reducing the formation of condensation on the radiating surface and/or cover and permitting the radiation to continue when the radiating surface is below the dewpoint of the atmosphere, and a housing supporting the radiating surface, cover and heat transfer means to an ice storage reservoir.

  4. Passive-solar directional-radiating cooling system

    DOE Patents [OSTI]

    Hull, John R. (Hinsdale, IL); Schertz, William W. (Batavia, IL)

    1986-01-01T23:59:59.000Z

    A radiative cooling system for use with an ice-making system having a radiating surface aimed at the sky for radiating energy at one or more wavelength bands for which the atmosphere is transparent and a cover thermally isolated from the radiating surface and transparent at least to the selected wavelength or wavelengths, the thermal isolation reducing the formation of condensation on the radiating surface and/or cover and permitting the radiation to continue when the radiating surface is below the dewpoint of the atmosphere, and a housing supporting the radiating surface, cover and heat transfer means to an ice storage reservoir.

  5. Thermal-mechanical Properties of Epoxy-impregnated Bi-2212/Ag Composite

    SciTech Connect (OSTI)

    Li, Pei; Wang, Yang; Godeke, Arno; Ye, Liyang; Flanagan, Gene; Shen, Tengming

    2014-11-26T23:59:59.000Z

    Knowledge of the thermal-mechanical properties of epoxy/superconductor/insulation composite is important for designing, fabricating, and operating epoxy impregnated high field superconducting magnets near their ultimate potentials. We report measurements of the modulus of elasticity, Poisson’s ratio, and the coefficient of thermal contraction of epoxy-impregnated composite made from the state-of-the-art powder-in-tube multifilamentary Ag/Bi2Sr2CaCu2Ox round wire at room temperature and cryogenic temperatures. Stress-strain curves of samples made from single-strand and Rutherford cables were tested under both monotonic and cyclic compressive loads, with single strands insulated using a thin TiO2 insulation coating and the Rutherford cable insulated with a braided ceramic sleeve.

  6. Interlaboratory comparison of the horizontal pipe insulation test apparatus up to 350{degrees}C

    SciTech Connect (OSTI)

    Whitaker, T.E. [Pabco, Fruita, CO (United States); Graves, R.S. [Oak Ridge National Lab., TN (United States); McElroy, D.L. [McElroy (David L.), Knoxville, TN (United States); Smith, D.R. [National Institute of Standards and Technology, Boulder, CO (United States)

    1993-12-01T23:59:59.000Z

    The purpose of this interlaboratory comparison was to provide information for the precision and bias section in the ASTM Standard Test Method C 335, {open_quotes}Steady-State Heat Transfer Properties of Horizontal Pipe Insulation.{close_quotes} (The text describes the ASTM C 335 test method, the specimens tested and the test protocol). The apparent thermal conductivity of two rigid calcium silicate pipe insulation specimens was measured by eight laboratories. Each laboratory measured both specimens at four different temperatures. The test mean temperatures ranged from 35 to 390{degrees}C. The two standard deviation value for the data ranged from 4.5 to 7.7% and the average value was 6.3%. The statement recommended for the precision and bias statement for Section 13.1.4 of ASTM C 335 is: {open_quotes}Tests performed at seven different laboratories using guarded-end horizontal pipe test apparatus and at one laboratory using an unguarded cylindrical screen test apparatus on two specimens of calcium silicate insulation in the range of mean temperatures from 35 to 390{degree}C did not vary by more than 6.3% (two standard deviations) of the average.{close_quotes}

  7. Development of large-capacity gas-insulated transformer

    SciTech Connect (OSTI)

    Takahashi, E.; Tanaka, K. [Tokyo Electric Power Co., Ltd. (Japan)] [Tokyo Electric Power Co., Ltd. (Japan); Toda, K.; Ikeda, M.; Teranishi, T.; Inaba, M.; Yanari, T. [Toshiba Corp., Kawasaki (Japan)] [Toshiba Corp., Kawasaki (Japan)

    1996-04-01T23:59:59.000Z

    Concentrations of population and business activities result in high electricity demand in urban areas. This requires the construction of large-capacity underground substations. Oilless, non-flammable and non-explosive equipment is recommended for underground substations. Therefore, several types of large-capacity gas-insulated transformer have been developed. Because the gas forced cooling type was considered to be available up to approximately 60 MVA, all of these gas-insulated transformers are liquid cooled. But the liquid cooling type has the disadvantage of a complex structure for liquid cooling. For this reason, the authors have been studying the development of a simple design for a gas forced cooling, large-capacity gas-insulated transformer. This paper discusses research and development of cooling and insulation technology for a large-capacity gas-insulated transformer and the development of a 275 kV, 300 MVA gas-insulated transformer.

  8. Explosion resistant insulator and method of making same

    DOE Patents [OSTI]

    Meyer, Jeffry R. (Penn Hills, PA); Billings, Jr., John S. (Trafford, PA); Spindle, Harvey E. (Wilkins Township, Allegheny County, PA); Hofmann, Charles F. (Export, PA)

    1983-01-01T23:59:59.000Z

    An electrical insulator assembly and method of manufacturing same, having a generally cylindrical or conical body portion formed of a breakable cast solid insulation system and a reinforcing member having a corrugated configuration and formed of a web or mesh type reinforcing fabric. When the breakable body member has been broken, the corrugated configured reinforcing web member provides a path of escape for pressurized insulating fluid while limiting the movement of body member fragments in the direction of escape of the pressurized fluid.

  9. High-temperature zirconia insulation and method for making same

    DOE Patents [OSTI]

    Wrenn, Jr., George E. (Clinton, TN); Holcombe, Jr., Cressie E. (Knoxville, TN); Lewis, Jr., John (Oak Ridge, TN)

    1988-01-01T23:59:59.000Z

    The present invention is directed to a highly pure, partially stabilized, fibrous zirconia composite for use as thermal insulation in environments where temperatures up to about 2000.degree. C. are utilized. The composite of the present invention is fabricated into any suitable configuration such as a cone, cylinder, dome or the like by vacuum molding an aqueous slurry of partially stabilized zirconia fibers into a desired configuration on a suitably shaped mandrel. The molded fibers are infiltrated with zirconyl nitrate and the resulting structure is then dried to form a rigid structure which may be removed and placed in a furnace. The structure is then heated in air to a temperature of about 600.degree. C. for driving off the nitrate from the structure and for oxidizing the zirconyl ion to zirconia. Thereafter, the structure is heated to about 950.degree. to 1,250.degree. C. to fuse the zirconia fibers at their nexi in a matrix of zirconia. The composite produced by the present invention is self-supporting and can be readily machined to desired final dimensions. Additional heating to about 1800.degree. to 2000.degree. C. further improves structural rigidity.

  10. High-temperature zirconia insulation and method for making same

    DOE Patents [OSTI]

    Wrenn, G.E. Jr.; Holcombe, C.E. Jr.; Lewis, J. Jr.

    1988-05-10T23:59:59.000Z

    The present invention is directed to a highly pure, partially stabilized, fibrous zirconia composite for use as thermal insulation in environments where temperatures up to about 2,000 C are utilized. The composite of the present invention is fabricated into any suitable configuration such as a cone, cylinder, dome or the like by vacuum molding an aqueous slurry of partially stabilized zirconia fibers into a desired configuration on a suitably shaped mandrel. The molded fibers are infiltrated with zirconyl nitrate and the resulting structure is then dried to form a rigid structure which may be removed and placed in a furnace. The structure is then heated in air to a temperature of about 600 C for driving off the nitrate from the structure and for oxidizing the zirconyl ion to zirconia. Thereafter, the structure is heated to about 950 to 1,250 C to fuse the zirconia fibers at their nexi in a matrix of zirconia. The composite produced by the present invention is self-supporting and can be readily machined to desired final dimensions. Additional heating to about 1,800 to 2,000 C further improves structural rigidity.

  11. Radiation: Radiation Control (Indiana)

    Broader source: Energy.gov [DOE]

    It is the policy of the state to encourage the constructive uses of radiation and to control its harmful effects. This section contains regulations pertaining to the manufacture, use,...

  12. Metal-Insulator Photocathode Heterojunction for Directed Electron...

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

    and low-intrinsic emittance electron pulses have been predicted for hybrid metal-insulator photocathode designs constructed from three to four monolayer MgO films on...

  13. A New Generation of Building Insulation by Foaming Polymer Blend...

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

    insulation technologies available on the market. Instead of hydroflurocarbon, it uses carbon dioxide as the blowing agent. This technology represents a highly valuable market...

  14. Highly Insulating Windows Volume Purchase Program Final Report

    SciTech Connect (OSTI)

    Parker, Graham B.; Mapes, Terry S.; Zalis, WJ

    2013-02-01T23:59:59.000Z

    This report summarizes the Highly Insulating Windows Volume Purchase Program, conduced by PNNL for DOE-BTP, including a summary of outcomes and lessons learned.

  15. Field Evaluation of Highly Insulating Windows in the Lab Homes: Winter Experiment

    SciTech Connect (OSTI)

    Parker, Graham B.; Widder, Sarah H.; Bauman, Nathan N.

    2012-06-01T23:59:59.000Z

    This field evaluation of highly insulating windows was undertaken in a matched pair of 'Lab Homes' located on the Pacific Northwest National Laboratory (PNNL) campus during the 2012 winter heating season. Improving the insulation and solar heat gain characteristics of a home's windows has the potential to significantly improve the home's building envelope and overall thermal performance by reducing heat loss (in the winter), and cooling loss and solar heat gain (in the summer) through the windows. A high quality installation and/or window retrofit will also minimize or reduce air leakage through the window cavity and thus also contribute to reduced heat loss in the winter and cooling loss in the summer. These improvements all contribute to decreasing overall annual home energy use. Occupant comfort (non-quantifiable) can also be increased by minimizing or eliminating the cold 'draft' (temperature) many residents experience at or near window surfaces that are at a noticeably lower temperature than the room air temperature. Lastly, although not measured in this experiment, highly insulating windows (triple-pane in this experiment) also have the potential to significantly reduce the noise transmittance through windows compared to standard double-pane windows. The metered data taken in the Lab Homes and data analysis presented here represent 70 days of data taken during the 2012 heating season. As such, the savings from highly insulating windows in the experimental home (Lab Home B) compared to the standard double-pane clear glass windows in the baseline home (Lab Home A) are only a portion of the energy savings expected from a year-long experiment that would include a cooling season. The cooling season experiment will take place in the homes in the summer of 2012, and results of that experiment will be reported in a subsequent report available to all stakeholders.

  16. Thermal sensor with an improved coating

    DOE Patents [OSTI]

    LaDelfe, Peter C. (Los Alamos, NM); Stotlar, Suzanne C. (Los Alamos, NM)

    1986-01-01T23:59:59.000Z

    The disclosure is directed to an apparatus for detecting radiation having wavelengths from about 0.4 .mu.m to about 5.6 .mu.m. An optical coating is applied to a thermal sensor that is normally transparent to radiation with such wavelengths. The optical coating is thin and light and includes a modifier and an absorber. The thermal sensor can be a pyroelectric detector such as strontium barium niobate.

  17. Thermal resistance of composite panels containing superinsulation and urethane foam

    SciTech Connect (OSTI)

    Wilkes, K.E.; Graves, R.S.; Childs, K.W.

    1996-09-01T23:59:59.000Z

    Laboratory data are presented on the thermal resistance of composite panels that incorporate superinsulation embedded in urethane foam. Composite panels were fabricated using four types of advanced insulations (three types of evacuated panel superinsulation and one type of gas-filled panel), and three foam blowing agents (CFC-11, HCFC-141b, and HCFC-142b/22 blend). Panels were also fabricated with only the urethane foam to serve as a baseline. Thermal measurements were performed using an ASTM C 518 Heat Flow Meter Apparatus. The thermal resistances of the panels were measured over a two-year period to detect whether any significant changes occurred. A computer model was used to analyze the data, adjusting for differences in size of the advanced insulations, and extrapolating to different sizes of composite panels.

  18. Thermal resistance of superinsulation/foam composite panels

    SciTech Connect (OSTI)

    Wilkes, K.E.; Graves, R.S.; Childs, K.W.

    1996-05-01T23:59:59.000Z

    Laboratory data are presented on the thermal resistance of composite panels that incorporate superinsulation embedded in urethane foam. Composite panels were fabricated using four types of advanced insulations (three types of evacuated panel superinsulation and one type of gas-filled panel), and three foam blowing agents (CFC-11, HCFC-141b, and HCFC-142b/22 blend). Panels were also fabricated with only the urethane foam to serve as a baseline. Thermal measurements were performed using an ASTM C 518 Heat Flow Meter Apparatus. The thermal resistances of the panels were measured over a two-year period to detect whether any significant changes occurred. A computer model was used to analyze the data, normalizing for differences in size of the advanced insulations, and extrapolating to different sizes of composite panels.

  19. Cloud Formation and Acceleration in a Radiative Environment

    E-Print Network [OSTI]

    Proga, Daniel

    2015-01-01T23:59:59.000Z

    In a radiatively heated and cooled medium, the thermal instability is a plausible mechanism for forming clouds, while the radiation force provides a natural acceleration, especially when ions recombine and opacity increases. Here we extend Field's theory to self-consistently account for a radiation force resulting from bound-free and bound-bound transitions in the optically thin limit. We present physical arguments for clouds to be significantly accelerated by a radiation force due to lines during a nonlinear phase of the instability. To qualitatively illustrate our main points, we perform both one and two-dimensional (1-D/2-D) hydrodynamical simulations that allow us to study the nonlinear outcome of the evolution of thermally unstable gas subjected to this radiation force. Our 1-D simulations demonstrate that the thermal instability can produce long-lived clouds that reach a thermal equilibrium between radiative processes and thermal conduction, while the radiation force can indeed accelerate the clouds to ...

  20. Objective: Determine the energy use of two greenhouse insulation technologies (a bubble insulation system and an energy/shade screen) retrofitted into plastic covered greenhouses, and compare the

    E-Print Network [OSTI]

    Vermont, University of

    Objective: Determine the energy use of two greenhouse insulation technologies (a bubble insulation structures. 1. Unimproved standard double-layer poly inflated greenhouse (control) 2. Bubble insulation is around 1-2, compared to an estimated 30 for the bubble system. What did we learn? The bubble insulation