National Library of Energy BETA

Sample records for r-value thermal resistance

  1. 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.

    1981-04-01

    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)

  2. Experimental study of thermal resistance values (R-values) of low-density mineral-fiber building insulation batts commercially available in 1977

    SciTech Connect (OSTI)

    Tye, R.P.; Desjarlais, A.O.; Yarbrough, D.W.; McElroy, D.L.

    1980-04-01

    This study was initiated in June 1977 to obtain and evaluate full-thickness thermal performance data on mineral fiber, i.e., fiberglass and rock wool, batt-type insulations. The study aimed to obtain full-thickness thermal performance data and to assess other properties of mineral fiber building insulations. The physical property measurements discussed in this report provide a measure of the range of values for density, thickness, and R-value based on a sampling of low-density mineral-fiber building insulation batts purchased in the marketplace in 1977. The experimental data were used to establish mean R-values at nominal (label) thickness of R-11 and R-19 fiberglass batts and R-11 rock wool batts. The full-thickness and sliced testing techniques provided a set of R-values on the purchased samples that were converted to R-values at label thickness by using a particular correlation of apparent thermal conductivity and density. The full thickness results indicate surprisingly large percentages below labeled R-value for these four types of mineral fiber insulation. A statistical analysis of these data based on the assumption of normally distributed properties is included. This yielded estimates of similar magnitude for the population from which the samples were purchased. An urgency for continued sampling and further testing of mineral fiber insulations by many laboratories was identified. The differences between results obtained with the sliced technique and results obtained with full-thickness testing must be thoroughly understood and documented so that adjustment factors for the thickness effect can be accurately established. (LCL)

  3. Thermal shock resistance ceramic insulator (Patent) | SciTech...

    Office of Scientific and Technical Information (OSTI)

    Patent: Thermal shock resistance ceramic insulator Citation Details In-Document Search Title: Thermal shock resistance ceramic insulator Thermal shock resistant cermet insulators ...

  4. Thermal Shock-resistant Cement

    SciTech Connect (OSTI)

    Sugama T.; Pyatina, T.; Gill, S.

    2012-02-01

    We studied the effectiveness of sodium silicate-activated Class F fly ash in improving the thermal shock resistance and in extending the onset of hydration of Secar #80 refractory cement. When the dry mix cement, consisting of Secar #80, Class F fly ash, and sodium silicate, came in contact with water, NaOH derived from the dissolution of sodium silicate preferentially reacted with Class F fly ash, rather than the #80, to dissociate silicate anions from Class F fly ash. Then, these dissociated silicate ions delayed significantly the hydration of #80 possessing a rapid setting behavior. We undertook a multiple heating -water cooling quenching-cycle test to evaluate the cement’s resistance to thermal shock. In one cycle, we heated the 200 and #61616;C-autoclaved cement at 500 and #61616;C for 24 hours, and then the heated cement was rapidly immersed in water at 25 and #61616;C. This cycle was repeated five times. The phase composition of the autoclaved #80/Class F fly ash blend cements comprised four crystalline hydration products, boehmite, katoite, hydrogrossular, and hydroxysodalite, responsible for strengthening cement. After a test of 5-cycle heat-water quenching, we observed three crystalline phase-transformations in this autoclaved cement: boehmite and #61614; and #61543;-Al2O3, katoite and #61614; calcite, and hydroxysodalite and #61614; carbonated sodalite. Among those, the hydroxysodalite and #61614; carbonated sodalite transformation not only played a pivotal role in densifying the cementitious structure and in sustaining the original compressive strength developed after autoclaving, but also offered an improved resistance of the #80 cement to thermal shock. In contrast, autoclaved Class G well cement with and without Class F fly ash and quartz flour failed this cycle test, generating multiple cracks in the cement. The major reason for such impairment was the hydration of lime derived from the dehydroxylation of portlandite formed in the autoclaved

  5. Thermal shock resistance ceramic insulator

    DOE Patents [OSTI]

    Morgan, Chester S. (Oak Ridge, TN); Johnson, William R. (Maynardville, TN)

    1980-01-01

    Thermal shock resistant cermet insulators containing 0.1-20 volume % metal present as a dispersed phase. The insulators are prepared by a process comprising the steps of (a) providing a first solid phase mixture of a ceramic powder and a metal precursor; (b) heating the first solid phase mixture above the minimum decomposition temperature of the metal precursor for no longer than 30 minutes and to a temperature sufficiently above the decomposition temperature to cause the selective decomposition of the metal precursor to the metal to provide a second solid phase mixture comprising particles of ceramic having discrete metal particles adhering to their surfaces, said metal particles having a mean diameter no more than 1/2 the mean diameter of the ceramic particles, and (c) densifying the second solid phase mixture to provide a cermet insulator having 0.1-20 volume % metal present as a dispersed phase.

  6. Borehole thermal resistance: Laboratory and field studies

    SciTech Connect (OSTI)

    Remund, C.P.

    1999-07-01

    Vertical ground heat exchangers are a common method of linking geothermal heat pump systems to the earth, and they consist of pipe installed into a borehole that is subsequently backfilled with a material that forms the heat transfer link between the pipe and earth. In many states that material must also be a grout to form a barrier against water migration in any direction along the entire borehole length. Until recently, little attention has been given to the thermal properties of commonly used backfill and grouting materials or to the effect of the thermal conductivity of those materials on the thermal performance of the vertical ground heat exchanger. Laboratory studies were performed to determine the effect of grout thermal conductivity, borehole diameter, pipe size, and pipe configuration on the total thermal resistance in the borehole. It was found that borehole thermal resistance decreased with increasing grout thermal resistance decreased with increasing grout thermal conductivity, but increasing grout thermal conductivity above 1.0 Btu/h{center{underscore}dot}ft{center{underscore}dot}{degree}F provided very small additional reduction. The studies resulted in a set of relationships for borehole thermal resistance, depending on the pipe configuration in the borehole, that can be utilized in the calculation of design length of a vertical ground heat exchanger for a prescribed heating and cooling load. A series of independent field tests verified that the assumption of equal spacing between the pipes and the borehole wall conservatively accounted for the thermal conductivity of the backfill or grout material. The effect of increasing grout thermal conductivity from 0.43 to 0.85 Btu/h{center{underscore}dot}ft{center{underscore}dot}{degree}F resulted in overall reductions in thermal resistance between the circulating fluid and the earth by 15.3% to 19.5%.

  7. Thermal shock resistance ceramic insulator (Patent) | SciTech...

    Office of Scientific and Technical Information (OSTI)

    Patent: Thermal shock resistance ceramic insulator Citation Details In-Document Search Title: Thermal shock resistance ceramic insulator You are accessing a document from the ...

  8. The Equivalent Thermal Resistance of Tile Roofs with and without Batten Systems

    SciTech Connect (OSTI)

    Miller, William A

    2013-01-01

    Clay and concrete tile roofs were installed on a fully instrumented attic test facility operating in East Tennessee s climate. Roof, attic and deck temperatures and heat flows were recorded for each of the tile roofs and also on an adjacent attic cavity covered with a conventionally pigmented and direct-nailed asphalt shingle roof. The data were used to benchmark a computer tool for simulation of roofs and attics and the tool used to develop an approach for computing an equivalent seasonal R-value for sub-tile venting. The approach computed equal heat fluxes through the ceilings of roofs having different combinations of surface radiation properties and or building constructions. A direct nailed shingle roof served as a control for estimating the equivalent thermal resistance of the air space. Simulations were benchmarked to data in the ASHRAE Fundamentals for the thermal resistance of inclined and closed air spaces.

  9. Thermal barrier coating resistant to sintering

    DOE Patents [OSTI]

    Subramanian, Ramesh; Sabol, Stephen M.

    2001-01-01

    A device (10) having a ceramic thermal barrier coating layer (16) characterized by a microstructure having gaps (18) with a sintering inhibiting material (22) disposed on the columns (20) within the gaps (18). The sintering resistant material (22) is stable over the range of operating temperatures of the device (10) and is not soluble with the underlying ceramic layer (16). For a YSZ ceramic layer (16) the sintering resistant layer (22) may preferably be aluminum oxide or yttrium aluminum oxide, deposited as a continuous layer or as nodules.

  10. Thermal barrier coating resistant to sintering

    DOE Patents [OSTI]

    Subramanian, Ramesh; Seth, Brij B.

    2004-06-29

    A device (10) is made, having a ceramic thermal barrier coating layer (16) characterized by a microstructure having gaps (18) with a sintering inhibiting material (22) disposed on the columns (20) within the gaps (18). The sintering resistant material (22) is stable over the range of operating temperatures of the device (10), is not soluble with the underlying ceramic layer (16) and is applied by a process that is not an electron beam physical vapor deposition process.

  11. Thermal barrier coating resistant to sintering

    DOE Patents [OSTI]

    Subramanian, Ramesh; Seth, Brig B.

    2005-08-23

    A device (10) is made, having a ceramic thermal barrier coating layer (16) characterized by a microstructure having gaps (18) with a sintering inhibiting material (22) disposed on the columns (20) within the gaps (18). The sintering resistant material (22) is stable over the range of operating temperatures of the device (10), is not soluble with the underlying ceramic layer (16) and is applied by a process that is not an electron beam physical vapor deposition process. The sintering inhibiting material (22) has a morphology adapted to improve the functionality of the sintering inhibiting material (22), characterized as continuous, nodule, rivulet, grain, crack, flake and combinations thereof and being disposed within at least some of the vertical and horizontal gaps.

  12. Low thermal resistance power module assembly

    DOE Patents [OSTI]

    Hassani, Vahab; Vlahinos, Andreas; Bharathan, Desikan

    2007-03-13

    A power module assembly with low thermal resistance and enhanced heat dissipation to a cooling medium. The assembly includes a heat sink or spreader plate with passageways or openings for coolant that extend through the plate from a lower surface to an upper surface. A circuit substrate is provided and positioned on the spreader plate to cover the coolant passageways. The circuit substrate includes a bonding layer configured to extend about the periphery of each of the coolant passageways and is made up of a substantially nonporous material. The bonding layer may be solder material which bonds to the upper surface of the plate to provide a continuous seal around the upper edge of each opening in the plate. The assembly includes power modules mounted on the circuit substrate on a surface opposite the bonding layer. The power modules are positioned over or proximal to the coolant passageways.

  13. Low thermal resistance power module assembly

    DOE Patents [OSTI]

    Hassani, Vahab; Vlahinos, Andreas; Bharathan, Desikan

    2010-12-28

    A power module assembly (400) with low thermal resistance and enhanced heat dissipation to a cooling medium. The assembly includes a heat sink or spreader plate (410) with passageways or openings (414) for coolant that extend through the plate from a lower surface (411) to an upper surface (412). A circuit substrate (420) is provided and positioned on the spreader plate (410) to cover the coolant passageways. The circuit substrate (420) includes a bonding layer (422) configured to extend about the periphery of each of the coolant passageways and is made up of a substantially nonporous material. The bonding layer (422) may be solder material which bonds to the upper surface (412) of the plate to provide a continuous seal around the upper edge of each opening (414) in the plate. The assembly includes power modules (430) mounted on the circuit substrate (420) on a surface opposite the bonding layer (422). The power modules (430) are positioned over or proximal to the coolant passageways.

  14. Moisture Management for High R-Value Walls

    SciTech Connect (OSTI)

    Lepage, R.; Schumacher, C.; Lukachko, A.

    2013-11-01

    This report explains the moisture-related concerns for high R-value wall assemblies and discusses past Building America research work that informs this study. In this project, hygrothermal simulations were prepared for several common approaches to High R-value wall construction in six cities (Houston, Atlanta, Seattle, St. Louis, Chicago, and International Falls) representing a range of climate zones. The modeling program assessed the moisture durability of the wall assemblies based on three primary sources of moisture: construction moisture, air leakage condensation, and bulk water leakage; the report presents results of the study.

  15. Thicknesses, densities, and calculated thermal resistances for loose-fill rock wool installed in two attic sections of a manufactured house

    SciTech Connect (OSTI)

    Graves, R.S.; Yarbrough, D.W.

    1986-02-01

    The effect of vibrations due to manufacturing and transport on the thickness, density, and calculated thermal resistance (R-value) of loose-fill rock wool insulation installed in two manufactured home units has been determined. Thickness and density measurements on blown attic insulation were made after installation, at the end of the manufacturing process, and after the units were towed 265 miles. These measurements were used to calculate R-values for the attic insulation. The end sections of the two units showed an overall insulation thickness decrease of about 16% and an average R-value change from 31.2 to 28.8 ft/sup 2/ x h x /sup 0/F/Btu. An estimated R-value greater than 30 ft/sup 2/ x h x /sup 0/F/Btu resulted from averaging the end and middle sections of the two units. The effect of reduced thickness along the edges of the attic space was not included in the estimate.

  16. Ultra low thermal expansion, highly thermal shock resistant ceramic

    DOE Patents [OSTI]

    Limaye, Santosh Y.

    1996-01-01

    Three families of ceramic compositions having the given formula: .phi..sub.1+X Zr.sub.4 P.sub.6-2X Si.sub.2X O.sub.24, .phi..sub.1+X Zr.sub.4-2X Y.sub.2X P.sub.6 O.sub.24 and .phi..sub.1+X Zr.sub.4-X Y.sub.X P.sub.6-2X Si.sub.X O.sub.24 wherein .phi. is either Strontium or Barium and X has a value from about 0.2 to about 0.8 have been disclosed. Ceramics formed from these compositions exhibit very low, generally near neutral, thermal expansion over a wide range of elevated temperatures.

  17. Ultra low thermal expansion, highly thermal shock resistant ceramic

    DOE Patents [OSTI]

    Limaye, S.Y.

    1996-01-30

    Three families of ceramic compositions having the given formula: {phi}{sub 1+X}Zr{sub 4}P{sub 6{minus}2X}Si{sub 2X}O{sub 24}, {phi}{sub 1+X}Zr{sub 4{minus}2X}Y{sub 2X}P{sub 6}O{sub 24} and {phi}{sub 1+X}Zr{sub 4{minus}X}Y{sub X}P{sub 6{minus}2X}Si{sub X}O{sub 24} wherein {phi} is either strontium or barium and X has a value from about 0.2 to about 0.8 have been disclosed. Ceramics formed from these compositions exhibit very low, generally near neutral, thermal expansion over a wide range of elevated temperatures. 7 figs.

  18. Moisture Management for High R-Value Walls

    SciTech Connect (OSTI)

    Lepage, R.; Schumacher, C.; Lukachko, A.

    2013-11-01

    The following report explains the moisture-related concerns for High R-value wall assemblies and discusses past Building America research work that informs this study. Hygrothermal simulations were prepared for several common approaches to High R-value wall construction in six cities (Houston, Atlanta, Seattle, St. Louis, Chicago, and International Falls) representing a range of climate zones (2, 3, 4C, 4, 5A, and 7, respectively). The simulations are informed by experience gained from past research in this area and validated by field measurement and forensic experience. The modeling program was developed to assess the moisture durability of the wall assemblies based on three primary sources of moisture: construction moisture, air leakage condensation, and bulk water leakage. The peak annual moisture content of the wood based exterior sheathing was used to comparatively analyze the response to the moisture loads for each of the walls in each given city. Walls which experienced sheathing moisture contents between 20% and 28% were identified as risky, whereas those exceeding 28% were identified as very high risk. All of the wall assemblies perform well under idealized conditions. However, only the walls with exterior insulation, or cavity insulation which provides a hygrothermal function similar to exterior insulation, perform adequately when exposed to moisture loads. Walls with only cavity insulation are particularly susceptible to air leakage condensation. None of the walls performed well when a precipitation based bulk water leak was introduced to the backside of the sheathing, emphasizing the importance of proper flashing details.

  19. Optical device with low electrical and thermal resistance bragg reflectors

    DOE Patents [OSTI]

    Lear, Kevin L.

    1996-01-01

    A compound-semiconductor optical device and method. The optical device is provided with one or more asymmetrically-graded heterojunctions between compound semiconductor layers for forming a distributed Bragg reflector mirror having an improved electrical and thermal resistance. Efficient light-emitting devices such as light-emitting diodes, resonant-cavity light-emitting diodes, and vertical-cavity surface-emitting lasers may be formed according to the present invention, which may be applied to the formation of resonant-cavity photodetectors.

  20. Optical device with low electrical and thermal resistance Bragg reflectors

    DOE Patents [OSTI]

    Lear, K.L.

    1996-10-22

    A compound-semiconductor optical device and method are disclosed. The optical device is provided with one or more asymmetrically-graded heterojunctions between compound semiconductor layers for forming a distributed Bragg reflector mirror having an improved electrical and thermal resistance. Efficient light-emitting devices such as light-emitting diodes, resonant-cavity light-emitting diodes, and vertical-cavity surface-emitting lasers may be formed according to the present invention, which may be applied to the formation of resonant-cavity photodetectors. 16 figs.

  1. Highly defective oxides as sinter resistant thermal barrier coating

    DOE Patents [OSTI]

    Subramanian, Ramesh

    2005-08-16

    A thermal barrier coating material formed of a highly defective cubic matrix structure having a concentration of a stabilizer sufficiently high that the oxygen vacancies created by the stabilizer interact within the matrix to form multi-vacancies, thereby improving the sintering resistance of the material. The concentration of stabilizer within the cubic matrix structure is greater than that concentration of stabilizer necessary to give the matrix a peak ionic conductivity value. The concentration of stabilizer may be at least 30 wt. %. Embodiments include a cubic matrix of zirconia stabilized by at least 30-50 wt. % yttria, and a cubic matrix of hafnia stabilized by at least 30-50 wt. % gadolinia.

  2. Insulation Project Moves Toward Higher R-value

    Office of Energy Efficiency and Renewable Energy (EERE)

    Current commercially available insulation materials yield R-6 per inch or less with no major improvements in thermal performance since the 1970s. In collaboration with Firestone Building Products and NanoPore, an Oak Ridge National Laboratory (ORNL) team led by Kaushik Biswas and Andre Desjarlais continues to research prototype composite foam boards with modified atmosphere insulation (MAI) cores.

  3. Graphite having improved thermal stress resistance and method of preparation

    DOE Patents [OSTI]

    Kennedy, Charles R.

    1980-01-01

    An improved method for fabricating a graphite article comprises the steps of impregnating a coke article by first heating the coke article in contact with a thermoplastic pitch at a temperature within the range of 250.degree.-300.degree. C. at a pressure within the range of 200-2000 psig for at least 4-10 hours and then heating said article at a temperature within the range of 450.degree.-485.degree. C. at a pressure of 200-2000 psig for about 16-24 hours to provide an impregnated article; heating the impregnated article for sufficient time to carbonize the impregnant to provide a second coke article, and graphitizing the second coke article. A graphite having improved thermal stress resistance results when the coke to be impregnated contains 1-3 wt.% sulfur and no added puffing inhibitors. An additional improvement in thermal stress resistance is achieved when the second coke article is heated above about 1400.degree. C. at a rate of at least 10.degree. C./minute to a temperature above the puffing temperature.

  4. Characterization of Contact and Bulk Thermal Resistance of Laminations for Electric Machines

    SciTech Connect (OSTI)

    Cousineau, J. Emily; Bennion, Kevin; DeVoto, Doug; Mihalic, Mark; Narumanchi, Sreekant

    2015-06-30

    The ability to remove heat from an electric machine depends on the passive stack thermal resistances within the machine and the convective cooling performance of the selected cooling technology. This report focuses on the passive thermal design, specifically properties of the stator and rotor lamination stacks. Orthotropic thermal conductivity, specific heat, and density are reported. Four materials commonly used in electric machines were tested, including M19 (29 and 26 gauge), HF10, and Arnon 7 materials.

  5. Thermal engineering of non-local resistance in lateral spin valves

    SciTech Connect (OSTI)

    Kasai, S. Takahashi, Y. K.; Hirayama, S.; Mitani, S.; Hono, K.; Adachi, H.; Ieda, J.; Maekawa, S.

    2014-04-21

    We study the non-local spin transport in Permalloy/Cu lateral spin valves (LSVs) fabricated on thermally oxidized Si and MgO substrates. While these LSVs show the same magnitude of spin signals, significant substrate dependence of the baseline resistance was observed. The baseline resistance shows much weaker dependence on the inter-electrode distance than that of the spin transport observed in the Cu wires. A simple analysis of voltage-current characteristics in the baseline resistance indicates the observed result can be explained by a combination of the Peltier and Seebeck effects at the injector and detector junctions, suggesting the usage of high thermal conductivity substrate (or under-layer) is effective to reduce the baseline resistance.

  6. Study on the thermal resistance in secondary particles chain of silica aerogel by molecular dynamics simulation

    SciTech Connect (OSTI)

    Liu, M. [Institute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing100190 (China); Department of Physics, University of Chinese Academy of Sciences, Beijing 100049 (China); Qiu, L., E-mail: qiulin111@sina.com, E-mail: jzzhengxinghua@163.com; Zheng, X. H., E-mail: qiulin111@sina.com, E-mail: jzzhengxinghua@163.com; Zhu, J.; Tang, D. W. [Institute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing100190 (China)

    2014-09-07

    In this article, molecular dynamics simulation was performed to study the heat transport in secondary particles chain of silica aerogel. The two adjacent particles as the basic heat transport unit were modelled to characterize the heat transfer through the calculation of thermal resistance and vibrational density of states (VDOS). The total thermal resistance of two contact particles was predicted by non-equilibrium molecular dynamics simulations (NEMD). The defects were formed by deleting atoms in the system randomly first and performing heating and quenching process afterwards to achieve the DLCA (diffusive limited cluster-cluster aggregation) process. This kind of treatment showed a very reasonable prediction of thermal conductivity for the silica aerogels compared with the experimental values. The heat transport was great suppressed as the contact length increased or defect concentration increased. The constrain effect of heat transport was much significant when contact length fraction was in the small range (<0.5) or the defect concentration is in the high range (>0.5). Also, as the contact length increased, the role of joint thermal resistance played in the constraint of heat transport was increasing. However, the defect concentration did not affect the share of joint thermal resistance as the contact length did. VDOS of the system was calculated by numerical method to characterize the heat transport from atomic vibration view. The smaller contact length and greater defect concentration primarily affected the longitudinal acoustic modes, which ultimately influenced the heat transport between the adjacent particles.

  7. Characterization of Contact and Bulk Thermal Resistance of Laminations for Electric Machines

    SciTech Connect (OSTI)

    Cousineau, Emily; Bennion, Kevin; Devoto, Douglas; Naramanchi, Sreekant

    2015-07-06

    Thermal management for electric motors is important as the automotive industry continues to transition to more electrically dominant vehicle propulsion systems. The transition to more electrically dominant propulsion systems leads to higher-power duty cycles for electric-drive systems. Thermal constraints place significant limitations on how electric motors ultimately perform. As thermal management improves, there will be a direct trade-off among motor performance, efficiency, cost, and the sizing of electric motors to operate within the thermal constraints. During the development of thermal finite element analysis models and computational fluid dynamics models for electric motors, it was found that there was a lack of open literature detailing the thermal properties of key materials common in electric motors that are significant in terms of heat removal. The lack of available literature, coupled with the strong interest from industry in the passive-stack thermal measurement results, led to experiments to characterize the thermal contact resistance between motor laminations. We examined four lamination materials, including the commonly used 26 gauge and 29 gauge M19 materials, the HF10 and Arnon 7 materials. These latter two materials are thinner and reduce eddy currents responsible for core losses. We measured the thermal conductivity of the lamination materials and the thermal contact resistance between laminations in a stack, as well as investigated factors affecting contact resistance between laminations such as the contact pressure and surface finish. Lamination property data will be provided and we also develop a model to estimate the through-stack thermal conductivity for materials beyond those that were directly tested in this work. For example, at a clamping pressure of 138 kPa, the 29 gauge M19 material has a through-stack thermal conductivity of 1.68 W/m-K, and the contact resistance between laminations was measured to be 193 mm^2-K/W. The measured bulk

  8. Generalized Procedure for Improved Accuracy of Thermal Contact Resistance Measurements for Materials With Arbitrary Temperature-Dependent Thermal Conductivity

    SciTech Connect (OSTI)

    Sayer, Robert A.

    2014-06-26

    Thermal contact resistance (TCR) is most commonly measured using one-dimensional steady-state calorimetric techniques. In the experimental methods we utilized, a temperature gradient is applied across two contacting beams and the temperature drop at the interface is inferred from the temperature profiles of the rods that are measured at discrete points. During data analysis, thermal conductivity of the beams is typically taken to be an average value over the temperature range imposed during the experiment. Our generalized theory is presented and accounts for temperature-dependent changes in thermal conductivity. The procedure presented enables accurate measurement of TCR for contacting materials whose thermal conductivity is any arbitrary function of temperature. For example, it is shown that the standard technique yields TCR values that are about 15% below the actual value for two specific examples of copper and silicon contacts. Conversely, the generalized technique predicts TCR values that are within 1% of the actual value. The method is exact when thermal conductivity is known exactly and no other errors are introduced to the system.

  9. Corrosion-resistant coating prepared by the thermal decomposition of lithium permanganate

    SciTech Connect (OSTI)

    Ferrando, W.A.

    1999-09-01

    A ceramic, metal, or metal alloy surface is covered with lithium permanganate which is then thermally decomposed to produce a corrosion resistant coating on the surface. This coating serves as a primer coating which is preferably covered with an overcoat of a sealing paint.

  10. The effect of an anisotropic pressure of thermal particles on resistive wall mode stability

    SciTech Connect (OSTI)

    Berkery, J. W. Sabbagh, S. A.; Betti, R.; Guazzotto, L.; Manickam, J.

    2014-11-15

    The effect of an anisotropic pressure of thermal particles on resistive wall mode stability in tokamak fusion plasmas is derived through kinetic theory and assessed through calculation with the MISK code [B. Hu et al., Phys. Plasmas 12, 0?57301 (2005)]. The fluid anisotropy is treated as a small perturbation on the plasma equilibrium and modeled with a bi-Maxwellian distribution function. A complete stability treatment without an assumption of high frequency mode rotation leads to anisotropic kinetic terms in the dispersion relation in addition to anisotropy corrections to the fluid terms. With the density and the average pressure kept constant, when thermal particles have a higher temperature perpendicular to the magnetic field than parallel, the fluid pressure-driven ballooning destabilization term is reduced. Additionally, the stabilizing kinetic effects of the trapped thermal ions can be enhanced. Together these two effects can lead to a modest increase in resistive wall mode stability.

  11. Oxidation resistant high temperature thermal cycling resistant coatings on silicon-based substrates and process for the production thereof

    DOE Patents [OSTI]

    Sarin, V.K.

    1990-08-21

    An oxidation resistant, high temperature thermal cycling resistant coated ceramic article for ceramic heat engine applications is disclosed. The substrate is a silicon-based material, i.e. a silicon nitride- or silicon carbide-based monolithic or composite material. The coating is a graded coating of at least two layers: an intermediate AlN or Al[sub x]N[sub y]O[sub z] layer and an aluminum oxide or zirconium oxide outer layer. The composition of the coating changes gradually from that of the substrate to that of the AlN or Al[sub x]N[sub y]O[sub z] layer and further to the composition of the aluminum oxide or zirconium oxide outer layer. Other layers may be deposited over the aluminum oxide layer. A CVD process for depositing the graded coating on the substrate is also disclosed.

  12. Oxidation resistant high temperature thermal cycling resistant coatings on silicon-based substrates and process for the production thereof

    DOE Patents [OSTI]

    Sarin, Vinod K. (Lexington, MA)

    1990-01-01

    An oxidation resistant, high temperature thermal cycling resistant coated ceramic article for ceramic heat engine applications. The substrate is a silicon-based material, i.e. a silicon nitride- or silicon carbide-based monolithic or composite material. The coating is a graded coating of at least two layers: an intermediate AlN or Al.sub.x N.sub.y O.sub.z layer and an aluminum oxide or zirconium oxide outer layer. The composition of the coating changes gradually from that of the substrate to that of the AlN or Al.sub.x N.sub.y O.sub.z layer and further to the composition of the aluminum oxide or zirconium oxide outer layer. Other layers may be deposited over the aluminum oxide layer. A CVD process for depositing the graded coating on the substrate is also disclosed.

  13. Generalized Procedure for Improved Accuracy of Thermal Contact Resistance Measurements for Materials With Arbitrary Temperature-Dependent Thermal Conductivity

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Sayer, Robert A.

    2014-06-26

    Thermal contact resistance (TCR) is most commonly measured using one-dimensional steady-state calorimetric techniques. In the experimental methods we utilized, a temperature gradient is applied across two contacting beams and the temperature drop at the interface is inferred from the temperature profiles of the rods that are measured at discrete points. During data analysis, thermal conductivity of the beams is typically taken to be an average value over the temperature range imposed during the experiment. Our generalized theory is presented and accounts for temperature-dependent changes in thermal conductivity. The procedure presented enables accurate measurement of TCR for contacting materials whose thermalmore » conductivity is any arbitrary function of temperature. For example, it is shown that the standard technique yields TCR values that are about 15% below the actual value for two specific examples of copper and silicon contacts. Conversely, the generalized technique predicts TCR values that are within 1% of the actual value. The method is exact when thermal conductivity is known exactly and no other errors are introduced to the system.« less

  14. Resistivity measurements of halide-salt/MgO separators for thermal cells

    SciTech Connect (OSTI)

    Redey, L.; McParland, M. ); Guidotti, R. )

    1990-01-01

    Resistivities of 20 compositions of halide-salt/MgO mixtures (various selections and percentages of LiF, LiCl, LiBr, KCl, KBr, CsBr, and MgO) to be used in Li-alloy/metal sulfide cells have been measured at temperatures between the melting point of a particular mixture and 500{degrees}C. The resistivities were determined with cold-pressed electrolyte-binder pellets by using a special cell and DC measuring technique. Temperature, salt composition, and MgO content were found to have a strong influence on resistivity. These factors are listed in decreasing order of the magnitude of the effect. The fabrication density (porosity) of the pellet also has some effect on resistivity. These measured resistivities provide a data base to select optimum compositions of electrolyte-binder pellets for LiSi/FeS{sub 2} thermal batteries and to calculate area-specific resistances of these components for battery modeling and optimization. 5 refs., 7 figs.

  15. Intrinsic SiO{sub x}-based unipolar resistive switching memory. II. Thermal effects on charge transport and characterization of multilevel programing

    SciTech Connect (OSTI)

    Chang, Yao-Feng Chen, Ying-Chen; Chen, Yen-Ting; Wang, Yanzhen; Xue, Fei; Zhou, Fei; Lee, Jack C.; Fowler, Burt

    2014-07-28

    Multilevel programing and charge transport characteristics of intrinsic SiO{sub x}-based resistive switching memory are investigated using TaN/SiO{sub x}/n{sup ++}Si (MIS) and TiW/SiO{sub x}/TiW (MIM) device structures. Current transport characteristics of high- and low-resistance states (HRS and LRS) are studied in both device structures during multilevel operation. Analysis of device thermal response demonstrates that the effective electron energy barrier is strongly dependent on the resistance of the programed state, with estimates of 0.1?eV in the LRS and 0.6?eV in the HRS. Linear data fitting and conductance analyses indicate Poole-Frenkel emission or hopping conductance in the low-voltage region, whereas Fowler-Nordheim (F-N) or trap-assisted tunneling (TAT) is indicated at moderate voltage. Characterizations using hopping transport lead to hopping distance estimates of ?1?nm in the LRS for both device structures. Relative permittivity values (?{sub r}) were extracted using the Poole-Frenkel formulism and estimates of local filament temperature, where ?{sub r} values were ?80 in the LRS and ?4 in the HRS, suggesting a strongly polarized medium in the LRS. The onset of F-N tunneling or TAT corresponds to an observed overshoot in the I-V response with an estimated threshold of 1.6??0.2?V, in good agreement with reported electro-luminescence results for LRS devices. Resistive switching is discussed in terms of electrochemical reactions between common SiO{sub 2} defects, and specific defect energy levels are assigned to the dominant transitions in the I-V response. The overshoot response in the LRS is consistent with TAT through either the E?' oxygen vacancy or the hydrogen bridge defect, both of which are reported to have an effective bandgap of 1.7?eV. The SET threshold at ?2.5?V is modeled as hydrogen release from the (Si-H){sub 2} defect to generate the hydrogen bridge, and the RESET transition is modeled as an electrochemical reaction that re-forms (Si

  16. Corrosion resistance of stainless steels during thermal cycling in alkali nitrate molten salts.

    SciTech Connect (OSTI)

    Bradshaw, Robert W.; Goods, Steven Howard

    2001-09-01

    The corrosion behavior of three austenitic stainless steels was evaluated during thermal cycling in molten salt mixtures consisting of NaNO{sub 3} and KNO{sub 3}. Corrosion tests were conducted with Types 316, 316L and 304 stainless steels for more than 4000 hours and 500 thermal cycles at a maximum temperature of 565 C. Corrosion rates were determined by chemically descaling coupons. Metal losses ranged from 5 to 16 microns and thermal cycling resulted in moderately higher corrosion rates compared to isothermal conditions. Type 316 SS was somewhat more corrosion resistant than Type 304 SS in these tests. The effect of carbon content on corrosion resistance was small, as 316L SS corroded only slightly slower than 316 SS. The corrosion rates increased as the dissolved chloride content of the molten salt mixtures increased. Chloride concentrations approximating 1 wt.%, coupled with thermal cycling, resulted in linear weight loss kinetics, rather than parabolic kinetics, which described corrosion rates for all other conditions. Optical microscopy and electron microprobe analysis revealed that the corrosion products consisted of iron-chromium spinel, magnetite, and sodium ferrite, organized as separate layers. Microanalysis of the elemental composition of the corrosion products further demonstrated that the chromium content of the iron-chromium spinel layer was relatively high for conditions in which parabolic kinetics were observed. However, linear kinetics were observed when the spinel layer contained relatively little chromium.

  17. Corrosion and wear resistance of tungsten carbide-cobalt and tungsten carbide-cobalt-chromium thermal spray coatings

    SciTech Connect (OSTI)

    Quets, J.; Alford, J.R.

    1999-07-01

    Tungsten carbide thermal spray coatings provide wear surfaces to new and overhauled components for various industries. Their wear resistance is obtained by incorporating small tungsten carbide particles into a metal matrix. This presentation will show what parameters influence their corrosion resistance in the ASTM B-117 Salt Spray Corrosion Test,

  18. Resistance of fly ash-Portland cement blends to thermal shock

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Pyatina, Tatiana; Sugama, Toshifumi

    2015-09-11

    Thermal-shock resistance of high-content fly ash-Portland cement blends was tested in the following ways. Activated and non-activated blends with 80-90 % fly ash F (FAF) were left to set at room temperature, then hydrated for 24 hours at 85°C and 24-more hours at 300°C and tested in five thermal-shock cycles (600°C heat - 25°C water quenching). XRD, and thermal gravimetric analyses, along with calorimetric measurements and SEM-EDX tests demonstrated that the activated blends form more hydrates after 24 hours at 300°C, and achieve a higher short-term compressive strength than do non-activated ones. Sodium meta-silicate and sodaash engendered the concomitant hydrationmore » of OPC and FAF, with the formation of mixed crystalline FAF-OPC hydrates and FAF hydrates, such as garranite, analcime, and wairakite, along with the amorphous FAF hydration products. In SS-activated and non-activated blends separate OPC (tobermorite) and FAF (amorphous gel) hydrates with no mixed crystalline products formed. The compressive strength of all tested blends decreased by nearly 50% after 5 thermal-shock test cycles. These changes in the compressive strength were accompanied by a marked decrease in the intensities of XRD patterns of the crystalline hydrates after the thermalshock. As a result, there was no significant difference in the performance of the blends with different activators« less

  19. Resistance of fly ash-Portland cement blends to thermal shock

    SciTech Connect (OSTI)

    Pyatina, Tatiana; Sugama, Toshifumi

    2015-09-11

    Thermal-shock resistance of high-content fly ash-Portland cement blends was tested in the following ways. Activated and non-activated blends with 80-90 % fly ash F (FAF) were left to set at room temperature, then hydrated for 24 hours at 85°C and 24-more hours at 300°C and tested in five thermal-shock cycles (600°C heat - 25°C water quenching). XRD, and thermal gravimetric analyses, along with calorimetric measurements and SEM-EDX tests demonstrated that the activated blends form more hydrates after 24 hours at 300°C, and achieve a higher short-term compressive strength than do non-activated ones. Sodium meta-silicate and sodaash engendered the concomitant hydration of OPC and FAF, with the formation of mixed crystalline FAF-OPC hydrates and FAF hydrates, such as garranite, analcime, and wairakite, along with the amorphous FAF hydration products. In SS-activated and non-activated blends separate OPC (tobermorite) and FAF (amorphous gel) hydrates with no mixed crystalline products formed. The compressive strength of all tested blends decreased by nearly 50% after 5 thermal-shock test cycles. These changes in the compressive strength were accompanied by a marked decrease in the intensities of XRD patterns of the crystalline hydrates after the thermalshock. As a result, there was no significant difference in the performance of the blends with different activators

  20. The study of crack resistance of TiAlN coatings under mechanical loading and thermal cycle testing

    SciTech Connect (OSTI)

    Akulinkin, Alexandr Shugurov, Artur Sergeev, Viktor; Panin, Alexey; Cheng, C.-H.

    2015-10-27

    The effect of preliminary ion bombardment of 321 stainless steel substrate on crack resistance of TiAlN coatings at uniaxial tension and thermal cycling is studied. The ion-beam treatment of the substrate is shown to substantially improve the adhesion strength of the coatings that prevents their delamination and spalling under uniaxial tension. The resistance to crack propagation and spalling by the thermal shock is higher in the TiAlN coating deposited onto the substrate subjected to Ti ion bombardment as compared to that in the TiAlN coating deposited onto the initial substrate.

  1. Hotbox Test R-value Database and the Building Envelopes Program (BEP)

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

    The Building Envelopes Program at Oak Ridge National Laboratory (ORNL) is a program within the Buildings Technology Center (BTC), the premier U.S. research facility devoted to developing technologies that improve the energy efficiency and environmental compatibility of residential and commercial buildings. Our program is divided into two parts: building envelope research, which focuses on the structural elements that enclose a building (walls, roofs and foundations), and materials research, which concentrates on the materials within the envelope systems (such as insulation). The building envelope provides the thermal barrier between the indoor and outdoor environment, and its elements are the key determinants of a building's energy requirements that result from the climate where it is located. [copied from http://www.ornl.gov/sci/roofs+walls/

  2. Analytic solution for thermal resistance of regions bounded by concentric N-gons (N = 3,4,. )

    SciTech Connect (OSTI)

    Naterer, G.F. )

    1993-01-01

    The thermal resistance for steady-state, two-dimensional heat flow in internal regions bounded by concentric polygons with isothermal boundary conditions is computed by a conformal mapping procedure. The coordinate transformation functions in the complex plane and the heat conduction shape factors may be expressed in a closed form but they require numerical integration. The analytic approach generalizes solutions given for specific geometries such as the domain bounded by concentric squares and it may be extended to the limiting case of concentric cylinders. 9 refs.

  3. Silica and boron-containing ultraphosphate laser glass with low concentration quenching and improved thermal shock resistance

    DOE Patents [OSTI]

    Cook, Lee M.; Stokowski, Stanley E.

    1987-04-28

    Neodymium-doped phosphate glasses having a refractive index, nd>1.520; an Abbe number, Vd, <60; a density <3.0 g/cm.sup.3, a thermal expansion coefficient, .alpha., .ltoreq.110.times.10.sup.-7 .degree.C..sup.-1 ; a Young's Modulus, E, <70.times.10.sup.3 N/mm.sup.2 ; a Poisson's Ratio, .nu., <0.28; a thermal conductivity, K, >0.5 W/m.multidot.K, a thermal FOM=(1-.nu.).multidot.K/.alpha.E>0.7, consisting essentially of, in mol. %: P.sub.2 O.sub.5 : 40-70% SiO.sub.2 : 0-20% B.sub.2 O.sub.3 : 5-20% Sum SiO.sub.2 +B.sub.2 O.sub.3 : 5-35% Sum Li.sub.2 O+Na.sub.2 O+K.sub.2 O: 5-20% Sum La.sub.2 O.sub.3 +Nd.sub.2 O.sub.3 : 3-10% Sum MgO+CaO+SrO+BaO+ZnO: 0-10% and preferably containing an amount of Nd.sub.2 O.sub.3 effective for laser activity having an emission cross-section, .sigma., >3.5.times.10.sup.-20 cm.sup.2 ; a fluorescence linewidth (.DELTA..lambda..sub.f1)<23.5 nm; a first e-folding time of the Nd.sup.3+ fluorescence at 0.5 wt. % Nd.sub.2 O.sub.3 >375 .mu.sec, and a first e-folding time of the Nd.sup.3+ fluorescence at 10 wt. % >175 .mu.sec at 10 wt. %, have very low self-concentration quenching rates.

  4. Thermal Interface Materials for Power Electronics Applications: Preprint

    SciTech Connect (OSTI)

    Narumanchi, S.; Mihalic, M.; Kelly, K.; Eesley, G.

    2008-07-01

    The thermal resistance of the thermal interface material layer greatly affects the maximum temperature of the power electronics.

  5. Oxidation-resistant, solution-processed plasmonic Ni nanochain-SiO{sub x} (x < 2) selective solar thermal absorbers

    SciTech Connect (OSTI)

    Yu, Xiaobai; Wang, Xiaoxin; Liu, Jifeng; Zhang, Qinglin; Li, Juchuan

    2014-08-21

    Metal oxidation at high temperatures has long been a challenge in cermet solar thermal absorbers, which impedes the development of atmospherically stable, high-temperature, high-performance concentrated solar power (CSP) systems. In this work, we demonstrate solution-processed Ni nanochain-SiO{sub x} (x < 2) and Ni nanochain-SiO{sub 2} selective solar thermal absorbers that exhibit a strong anti-oxidation behavior up to 600 °C in air. The thermal stability is far superior to previously reported Ni nanoparticle-Al{sub 2}O{sub 3} selective solar thermal absorbers, which readily oxidize at 450 °C. The SiO{sub x} (x < 2) and SiO{sub 2} matrices are derived from hydrogen silsesquioxane and tetraethyl orthosilicate precursors, respectively, which comprise Si-O cage-like structures and Si-O networks. Fourier transform infrared spectroscopy shows that the dissociation of Si-O cage-like structures and Si-O networks at high temperatures have enabled the formation of new bonds at the Ni/SiO{sub x} interface to passivate the surface of Ni nanoparticles and prevent oxidation. X-ray photoelectron spectroscopy and Raman spectroscopy demonstrate that the excess Si in the SiO{sub x} (x < 2) matrices reacts with Ni nanostructures to form silicides at the interfaces, which further improves the anti-oxidation properties. As a result, Ni-SiO{sub x} (x < 2) systems demonstrate better anti-oxidation performance than Ni-SiO{sub 2} systems. This oxidation-resistant Ni nanochain-SiO{sub x} (x < 2) cermet coating also exhibits excellent high-temperature optical performance, with a high solar absorptance of ∼90% and a low emittance ∼18% measured at 300 °C. These results open the door towards atmospheric stable, high temperature, high-performance solar selective absorber coatings processed by low-cost solution-chemical methods for future generations of CSP systems.

  6. A nanostructure thermal property measurement platform. (Conference...

    Office of Scientific and Technical Information (OSTI)

    side of the central heater), and this feature permits identification of possible changes in thermal conductance along the wire and measurement of the thermal contact resistance. ...

  7. Effectiveness of thermal insulation in the attic spaces of manufactured homes

    SciTech Connect (OSTI)

    Yarbrough, D.W.; Graves, R.S.; McElroy, D.L.

    1988-01-01

    The thermal resistance of loose-fill insulations is reduced by settling that occurs after installation. The use of loose-fill insulation in manufactured homes is increasing and a need exists to evaluate the effectiveness of this application. Settling of loose- fill insulation in manufactured homes occurs during construction and over-the-road delivery. Measurements of the settling of a stabilized cellulosic insulation in four units has shown that a small amount of adhesive results in a product exhibiting 3 to 5% loss of thickness during manufacture and less than 2% additional settling during delivery. This thickness loss of about 6% is small in comparison with the unstabilized loose-fill rock wool that was observed in two units. The effectiveness of attic insulations in manufactured home units is significantly affected by the limited space available in many designs. Calculations of the thermal resistance that can be achieved in typical attics will be discussed. The results are that loose-fill materials are a better choice than batts for manufactured home attic insulation when truss design prevents complete coverage and that attic design must be improved in many cases in order to achieve specified R-values. 6 refs., 14 figs., 2 tabs.

  8. Energy Efficiency in Log Homes | Department of Energy

    Office of Environmental Management (EM)

    or purchasing a manufactured log home, you should consider several factors related to energy efficiency. The R-Value of Wood A material's thermal resistance or resistance to...

  9. Freeze resistant buoy system

    DOE Patents [OSTI]

    Hill, David E [Knoxville, TN; Greenbaum, Elias [Knoxville, TN

    2007-08-21

    A freeze resistant buoy system includes a tail-tube buoy having a thermally insulated section disposed predominantly above a waterline, and a thermo-siphon disposed predominantly below the waterline.

  10. Resisting Bacterial Resistance

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

    Resisting Bacterial Resistance 1663 Los Alamos science and technology magazine Latest Issue:July 2016 past issues All Issues » submit Resisting Bacterial Resistance Los Alamos scientists are taking an in-depth look at how bacteria defeat death-by-antibiotics. March 8, 2016 Artist rendering of green bacteria Gram-negative bacteria have evolved multiple strategies for self-defense-including mechanisms to pump out any molecules that could kill them, such as antibiotics. "We want to ensure

  11. High-Performance Corrosion-Resistant Materials: Iron-Based Amorphous-Metal Thermal-Spray Coatings: SAM HPCRM Program ? FY04 Annual Report ? Rev. 0 - DARPA DSO & DOE OCRWM Co-Sponsored Advanced Materials Program

    SciTech Connect (OSTI)

    Farmer, J; Haslam, J; Wong, F; Ji, S; Day, S; Branagan, D; Marshall, M; Meacham, B; Buffa, E; Blue, C; Rivard, J; Beardsley, M; Buffa, E; Blue, C; Rivard, J; Beardsley, M; Weaver, D; Aprigliano, L; Kohler, L; Bayles, R; Lemieux, E; Wolejsza, T; Martin, F; Yang, N; Lucadamo, G; Perepezko, J; Hildal, K; Kaufman, L; Heuer, A; Ernst, F; Michal, G; Kahn, H; Lavernia, E

    2007-09-19

    The multi-institutional High Performance Corrosion Resistant Materials (HPCRM) Team is cosponsored by the Defense Advanced Projects Agency (DARPA) Defense Science Office (DSO) and the Department of Energy (DOE) Office of Civilian Radioactive Waste Management (OCRWM), and has developed new corrosion-resistant, iron-based amorphous metals that can be applied as coatings with advanced thermal spray technology. Two compositions have corrosion resistance superior to wrought nickel-based Alloy C-22 (UNS No. N06022) in very aggressive environments, including concentrated calcium-chloride brines at elevated temperature. Corrosion costs the Department of Defense billions of dollars every year, with an immense quantity of material in various structures undergoing corrosion. For example, in addition to fluid and seawater piping, ballast tanks, and propulsions systems, approximately 345 million square feet of structure aboard naval ships and crafts require costly corrosion control measures. The use of advanced corrosion-resistant materials to prevent the continuous degradation of this massive surface area would be extremely beneficial. The Fe-based corrosion-resistant, amorphous-metal coatings under development may prove of importance for applications on ships. Such coatings could be used as an 'integral drip shield' on spent fuel containers, as well as protective coatings that could be applied over welds, thereby preventing exposure to environments that might cause stress corrosion cracking. In the future, such new high-performance iron-based materials could be substituted for more-expensive nickel-based alloys, thereby enabling a reduction in the $58-billion life cycle cost for the long-term storage of the Nation's spent nuclear fuel by tens of percent.

  12. Tunable Thermal Link - Energy Innovation Portal

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

    Tunable Thermal Link Lawrence Berkeley National Laboratory Contact LBL About This Technology Technology Marketing SummaryThermal links are incorporated into everything from frying pans to internal combustion engine spark plugs and heat sinks on integrated circuit boards. Typically, the link's thermal resistance is fixed and cannot be tuned after manufacture. While the ability to tune electrical resistors is widespread, virtually no tunable thermal resistance link exists, which has held back the

  13. In-situ x-ray diffraction and resistivity analysis of CoSi{sub 2} phase formation with and without a Ti interlayer at rapid thermal annealing rates

    SciTech Connect (OSTI)

    Cabral, C. Jr.; Clevenger, L.A.; Stephenson, G.B.; Brauer, S.; Morales, G.; Ludwig, K.F. Jr.

    1995-09-01

    It has been demonstrated, using synchrotron radiation, that at rapid thermal annealing rates (3 C/s) the 2formation of CoSi{sub 2} shifts to higher temperatures when a thin Ti interlayer is placed between Co and polycrystalline Si. It has also been shown that the Ti interlayer reduces the temperature range between the start of CoSi formation and CoSi{sub 2} formation (i.e. the range over which CoSi is present). 13 nm of Co deposited by physical vapor deposition on polycrystalline Si with and without either a 2 nm or 3.4 nm interlayer of Ti was analyzed in-situ by monitoring x-ray diffraction (XRD) peak intensity as a function of temperature using monochromatic radiation from a synchrotron beam line and by monitoring resistivity as a function of temperature i a rapid thermal annealing (RTA) system. The XRD analysis indicates that the phase formation proceeds from CoSi to CoSi{sub 2} in a temperature range that decreases from about 200 C to 140 C to 115 C with pure Co, Co/2 nm Ti and Co/3.4 nm Ti films respectively. The onset of the CoSi formation increases by about 135 C and 160 C for Co/2 nm Ti and Co/3.4 nm Ti compared to pure Co. The CoSi temperature range decreases from about 75 C in pure Co to less than 50 C in Co/Ti. In-situ RTA resistance along with in-situ XRD analysis indicates that the onset formation temperatures for CoSi are about 440 C, 575 C and 600 C and the temperatures for the completion of CoSi{sub 2} formation are about 640 C, 715 C and 715 C for Co, Co/2 nm Ti and Co/3.4 nm Ti films respectively. The results are consistent with he Ti interlayer acting as a diffusion barrier during the initial stages of the Co-Si reaction.

  14. Methods for resistive switching of memristors

    DOE Patents [OSTI]

    Mickel, Patrick R.; James, Conrad D.; Lohn, Andrew; Marinella, Matthew; Hsia, Alexander H.

    2016-05-10

    The present invention is directed generally to resistive random-access memory (RRAM or ReRAM) devices and systems, as well as methods of employing a thermal resistive model to understand and determine switching of such devices. In particular example, the method includes generating a power-resistance measurement for the memristor device and applying an isothermal model to the power-resistance measurement in order to determine one or more parameters of the device (e.g., filament state).

  15. Thermal Sciences

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

    Thermal Sciences NETL's Thermal Sciences competency provides the scientific, engineering, and technology development community with innovative and efficient approaches to measure, harness, and convert thermal energy. Research includes sensors, advanced energy concepts, and thermodynamic optimization, specifically: Sensors and Diagnostics Advanced sensor and diagnostic technology to develop and evaluate advanced methods for non-intrusive measurement and measurement in extreme environments.

  16. Abrasion resistant heat pipe

    DOE Patents [OSTI]

    Ernst, Donald M. (Leola, PA)

    1984-10-23

    A specially constructed heat pipe for use in fluidized bed combustors. Two distinct coatings are spray coated onto a heat pipe casing constructed of low thermal expansion metal, each coating serving a different purpose. The first coating forms aluminum oxide to prevent hydrogen permeation into the heat pipe casing, and the second coating contains stabilized zirconium oxide to provide abrasion resistance while not substantially affecting the heat transfer characteristics of the system.

  17. Abrasion resistant heat pipe

    DOE Patents [OSTI]

    Ernst, D.M.

    1984-10-23

    A specially constructed heat pipe is described for use in fluidized bed combustors. Two distinct coatings are spray coated onto a heat pipe casing constructed of low thermal expansion metal, each coating serving a different purpose. The first coating forms aluminum oxide to prevent hydrogen permeation into the heat pipe casing, and the second coating contains stabilized zirconium oxide to provide abrasion resistance while not substantially affecting the heat transfer characteristics of the system.

  18. Rapid Thermal Pyrolysis of Interferometrically Patterned Resist...

    Office of Scientific and Technical Information (OSTI)

    (SNL-NM), Albuquerque, NM (United States) Sponsoring Org: USDOE National Nuclear Security Administration (NNSA) Country of Publication: United States Language: English...

  19. Project Profile: Novel Thermal Energy Storage Systems for Concentratin...

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

    Energy Storage Systems for Concentrating Solar Power Project Profile: Novel Thermal Energy ... reduce thermal resistances within the TES system of a large-scale CSP plant and, in turn, ...

  20. Oxidation-resistant, solution-processed plasmonic Ni nanochain...

    Office of Scientific and Technical Information (OSTI)

    Oxidation-resistant, solution-processed plasmonic Ni nanochain-SiOsub x (x < 2) selective solar thermal absorbers Citation Details In-Document Search Title: Oxidation-resistant, ...

  1. Experimental and numerical study of the effective thermal conductivity...

    Office of Scientific and Technical Information (OSTI)

    to describe interface resistance of particles in modern TIMs, aka particulate composites. ... Country of Publication: United States Language: English Subject: Thermal Conductivity; ...

  2. DC Resistivity Survey (Wenner Array) | Open Energy Information

    Open Energy Info (EERE)

    faults Hydrological: Resistivity influenced by porosity, grain size distribution, permeability, fluid saturation, fluid type and phase state of the pore water Thermal:...

  3. Fire resistant nuclear fuel cask

    DOE Patents [OSTI]

    Heckman, Richard C.; Moss, Marvin

    1979-01-01

    The disclosure is directed to a fire resistant nuclear fuel cask employing reversibly thermally expansible bands between adjacent cooling fins such that normal outward flow of heat is not interfered with, but abnormal inward flow of heat is impeded or blocked.

  4. Thermal barrier coatings

    DOE Patents [OSTI]

    Alvin, Mary Anne

    2010-06-22

    This disclosure addresses the issue of providing a metallic-ceramic overlay coating that potentially serves as an interface or bond coat layer to provide enhanced oxidation resistance to the underlying superalloy substrate via the formation of a diffusion barrier regime within the supporting base material. Furthermore, the metallic-ceramic coating is expected to limit the growth of a continuous thermally grown oxide (TGO) layer that has been primarily considered to be the principal cause for failure of existing TBC systems. Compositional compatibility of the metallic-ceramic with traditional yttria-stabilized zirconia (YSZ) top coats is provided to further limit debond or spallation of the coating during operational use. A metallic-ceramic architecture is disclosed wherein enhanced oxidation resistance is imparted to the surface of nickel-based superalloy or single crystal metal substrate, with simultaneous integration of the yttria stabilized zirconia (YSZ) within the metallic-ceramic overlayer.

  5. Thermal indicator for wells

    DOE Patents [OSTI]

    Gaven, Jr., Joseph V.; Bak, Chan S.

    1983-01-01

    Minute durable plate-like thermal indicators are employed for precision measuring static and dynamic temperatures of well drilling fluids. The indicators are small enough and sufficiently durable to be circulated in the well with drilling fluids during the drilling operation. The indicators include a heat resistant indicating layer, a coacting meltable solid component and a retainer body which serves to unitize each indicator and which may carry permanent indicator identifying indicia. The indicators are recovered from the drilling fluid at ground level by known techniques.

  6. Resistivity analysis

    DOE Patents [OSTI]

    Bruce, Michael R.; Bruce, Victoria J.; Ring, Rosalinda M.; Cole, Edward Jr. I.; Hawkins, Charles F.; Tangyungong, Paiboon

    2006-06-13

    According to an example embodiment of the present invention a semiconductor die having a resistive electrical connection is analyzed. Heat is directed to the die as the die is undergoing a state-changing operation to cause a failure due to suspect circuitry. The die is monitored, and a circuit path that electrically changes in response to the heat is detected and used to detect that a particular portion therein of the circuit is resistive. In this manner, the detection and localization of a semiconductor die defect that includes a resistive portion of a circuit path is enhanced.

  7. Thermal conductivity measurements of Summit polycrystalline silicon.

    SciTech Connect (OSTI)

    Clemens, Rebecca; Kuppers, Jaron D.; Phinney, Leslie Mary

    2006-11-01

    A capability for measuring the thermal conductivity of microelectromechanical systems (MEMS) materials using a steady state resistance technique was developed and used to measure the thermal conductivities of SUMMiT{trademark} V layers. Thermal conductivities were measured over two temperature ranges: 100K to 350K and 293K to 575K in order to generate two data sets. The steady state resistance technique uses surface micromachined bridge structures fabricated using the standard SUMMiT fabrication process. Electrical resistance and resistivity data are reported for poly1-poly2 laminate, poly2, poly3, and poly4 polysilicon structural layers in the SUMMiT process from 83K to 575K. Thermal conductivity measurements for these polysilicon layers demonstrate for the first time that the thermal conductivity is a function of the particular SUMMiT layer. Also, the poly2 layer has a different variation in thermal conductivity as the temperature is decreased than the poly1-poly2 laminate, poly3, and poly4 layers. As the temperature increases above room temperature, the difference in thermal conductivity between the layers decreases.

  8. Quantification of corrosion resistance of a new-class of criticality control materials: thermal-spray coatings of high-boron iron-based amorphous metals - Fe49.7Cr17.7Mn1.9Mo7.4W1.6B15.2C3.8Si2.4

    SciTech Connect (OSTI)

    Farmer, J C; Choi, J S; Shaw, C K; Rebak, R; Day, S D; Lian, T; Hailey, P; Payer, J H; Branagan, D J; Aprigliano, L F

    2007-03-28

    An iron-based amorphous metal, Fe{sub 49.7}Cr{sub 17.7}Mn{sub 1.9}Mo{sub 7.4}W{sub 1.6}B{sub 15.2}C{sub 3.8}Si{sub 2.4} (SAM2X5), with very good corrosion resistance was developed. This material was produced as a melt-spun ribbon, as well as gas atomized powder and a thermal-spray coating. Chromium (Cr), molybdenum (Mo) and tungsten (W) provided corrosion resistance, and boron (B) enabled glass formation. The high boron content of this particular amorphous metal made it an effective neutron absorber, and suitable for criticality control applications. Earlier studies have shown that ingots and melt-spun ribbons of these materials have good passive film stability in these environments. Thermal spray coatings of these materials have now been produced, and have undergone a variety of corrosion testing, including both atmospheric and long-term immersion testing. The modes and rates of corrosion have been determined in the various environments, and are reported here.

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

    SciTech Connect (OSTI)

    Harris, Michael T.; Basaran, Osman A.; Kollie, Thomas G.; Weaver, Fred J.

    1995-01-01

    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

    SciTech Connect (OSTI)

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

    1996-01-02

    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.

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

    SciTech Connect (OSTI)

    Harris, Michael T.; Basaran, Osman A.; Kollie, Thomas G.; Weaver, Fred J.

    1994-01-01

    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. Silica powders for powder evacuated thermal insulating panel and method

    SciTech Connect (OSTI)

    Harris, Michael T.; Basaran, Osman A.; Kollie, Thomas G.; Weaver, Fred J.

    1996-01-01

    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.

  13. Thermal battery

    SciTech Connect (OSTI)

    Williams, M.T.; Winchester, C.S.; Jolson, J.D.

    1989-06-20

    A thermal battery is described comprising at least one electrochemical cell comprising an anode of alkali metal, alkaline earth metal or alloys thereof, a fusible salt electrolyte, a fluorocarbon polymer or fluorochlorocarbon polymer depolarizer, and means for heating the cell to melt the electrolyte.

  14. Heat transmission between a profiled nanowire and a thermal bath

    SciTech Connect (OSTI)

    Blanc, Christophe; Heron, Jean-Savin; Fournier, Thierry; Bourgeois, Olivier

    2014-07-28

    Thermal transport through profiled and abrupt contacts between a nanowire and a reservoir has been investigated by thermal conductance measurements. It is demonstrated that above 1?K the transmission coefficients are identical between abrupt and profiled junctions. This shows that the thermal transport is principally governed by the nanowire itself rather than by the resistance of the thermal contact. These results are perfectly compatible with the previous theoretical models. The thermal conductance measured at sub-Kelvin temperatures is discussed in relation to the universal value of the quantum of thermal conductance.

  15. DC Resistivity Survey (Mise-A-La-Masse) | Open Energy Information

    Open Energy Info (EERE)

    fluid type and phase state of the pore water Thermal: Resistivity influenced by temperature Dictionary.png DC Resistivity Survey (Mise-A-La-Masse): No definition has been...

  16. Pre-resistance-welding resistance check

    DOE Patents [OSTI]

    Destefan, Dennis E.; Stompro, David A.

    1991-01-01

    A preweld resistance check for resistance welding machines uses an open circuited measurement to determine the welding machine resistance, a closed circuit measurement to determine the parallel resistance of a workpiece set and the machine, and a calculation to determine the resistance of the workpiece set. Any variation in workpiece set or machine resistance is an indication that the weld may be different from a control weld.

  17. Single-Well and Cross-Well Resistivity | Open Energy Information

    Open Energy Info (EERE)

    faults Hydrological: Resistivity influenced by porosity, grain size distribution, permeability, fluid saturation, fluid type and phase state of the pore water Thermal:...

  18. Direct-Current Resistivity Survey | Open Energy Information

    Open Energy Info (EERE)

    fluid type and phase state of the pore water. Thermal: Resistivity influenced by temperature.1 Cost Information Low-End Estimate (USD): 4,827.00482,700 centUSD 4.827...

  19. Electrical and thermal conductivities in dense plasmas

    SciTech Connect (OSTI)

    Faussurier, G. Blancard, C.; Combis, P.; Videau, L.

    2014-09-15

    Expressions for the electrical and thermal conductivities in dense plasmas are derived combining the Chester-Thellung-Kubo-Greenwood approach and the Kramers approximation. The infrared divergence is removed assuming a Drude-like behaviour. An analytical expression is obtained for the Lorenz number that interpolates between the cold solid-state and the hot plasma phases. An expression for the electrical resistivity is proposed using the Ziman-Evans formula, from which the thermal conductivity can be deduced using the analytical expression for the Lorenz number. The present method can be used to estimate electrical and thermal conductivities of mixtures. Comparisons with experiment and quantum molecular dynamics simulations are done.

  20. Thermal Performance and Reliability Characterization of Bonded Interface Materials (BIMs): Preprint

    SciTech Connect (OSTI)

    DeVoto, D.; Paret, P.; Mihalic, M.; Narumanchi, S.; Bar-Cohen, A.; Matin, K.

    2014-08-01

    Thermal interface materials are an important enabler for low thermal resistance and reliable electronics packaging for a wide array of applications. There is a trend towards bonded interface materials (BIMs) because of their potential for low thermal resistivity (< 1 mm2K/W). However, BIMs induce thermomechanical stresses in the package and can be prone to failures and integrity risks. Deteriorated interfaces can result in high thermal resistance in the package and degradation and/or failure of the electronics. DARPA's Thermal Management Technologies program has addressed this challenge, supporting the development of mechanically-compliant, low resistivity nano-thermal interface (NTI) materials. In this work, we describe the testing procedure and report the results of NREL's thermal performance and reliability characterization of an initial sample of four different NTI-BIMs.

  1. Thermal conductivity of thermal-battery insulations

    SciTech Connect (OSTI)

    Guidotti, R.A.; Moss, M.

    1995-08-01

    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.

  2. High thermal conductivity connector having high electrical isolation

    DOE Patents [OSTI]

    Nieman, Ralph C.; Gonczy, John D.; Nicol, Thomas H.

    1995-01-01

    A method and article for providing a low-thermal-resistance, high-electrical-isolation heat intercept connection. The connection method involves clamping, by thermal interference fit, an electrically isolating cylinder between an outer metallic ring and an inner metallic disk. The connection provides durable coupling of a heat sink and a heat source.

  3. Validation of thermal models for a prototypical MEMS thermal actuator.

    SciTech Connect (OSTI)

    Gallis, Michail A.; Torczynski, John Robert; Piekos, Edward Stanley; Serrano, Justin Raymond; Gorby, Allen D.; Phinney, Leslie Mary

    2008-09-01

    This report documents technical work performed to complete the ASC Level 2 Milestone 2841: validation of thermal models for a prototypical MEMS thermal actuator. This effort requires completion of the following task: the comparison between calculated and measured temperature profiles of a heated stationary microbeam in air. Such heated microbeams are prototypical structures in virtually all electrically driven microscale thermal actuators. This task is divided into four major subtasks. (1) Perform validation experiments on prototypical heated stationary microbeams in which material properties such as thermal conductivity and electrical resistivity are measured if not known and temperature profiles along the beams are measured as a function of electrical power and gas pressure. (2) Develop a noncontinuum gas-phase heat-transfer model for typical MEMS situations including effects such as temperature discontinuities at gas-solid interfaces across which heat is flowing, and incorporate this model into the ASC FEM heat-conduction code Calore to enable it to simulate these effects with good accuracy. (3) Develop a noncontinuum solid-phase heat transfer model for typical MEMS situations including an effective thermal conductivity that depends on device geometry and grain size, and incorporate this model into the FEM heat-conduction code Calore to enable it to simulate these effects with good accuracy. (4) Perform combined gas-solid heat-transfer simulations using Calore with these models for the experimentally investigated devices, and compare simulation and experimental temperature profiles to assess model accuracy. These subtasks have been completed successfully, thereby completing the milestone task. Model and experimental temperature profiles are found to be in reasonable agreement for all cases examined. Modest systematic differences appear to be related to uncertainties in the geometric dimensions of the test structures and in the thermal conductivity of the

  4. High Temperature Thermal Array for Next Generation Solar Thermal...

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

    High Temperature Thermal Array for Next Generation Solar Thermal Power Production High Temperature Thermal Array for Next Generation Solar Thermal Power Production This ...

  5. Effects of thermal fluctuations on thermal inflation

    SciTech Connect (OSTI)

    Hiramatsu, Takashi; Miyamoto, Yuhei; Yokoyama, Jun’ichi

    2015-03-12

    The mechanism of thermal inflation, a relatively short period of accelerated expansion after primordial inflation, is a desirable ingredient for a certain class of particle physics models if they are not to be in contention with the cosmology of the early Universe. Though thermal inflation is most simply described in terms of a thermal effective potential, a thermal environment also gives rise to thermal fluctuations that must be taken into account. We numerically study the effects of these thermal fluctuations using lattice simulations. We conclude that though they do not ruin the thermal inflation scenario, the phase transition at the end of thermal inflation proceeds through phase mixing and is therefore not accompanied by the formations of bubbles nor appreciable amplitude of gravitational waves.

  6. Turbine Thermal Management

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

    Turbine Thermal Management Fact Sheets Research Team Members Key Contacts Turbine Thermal Management The gas turbine is the workhorse of power generation, and technology advances ...

  7. Thermal Control & System Integration

    Broader source: Energy.gov [DOE]

    The thermal control and system integration activity focuses on issues such as the integration of motor and power control technologies and the development of advanced thermal control technologies....

  8. Methods for enhancing mapping of thermal fronts in oil recovery

    DOE Patents [OSTI]

    Lee, D.O.; Montoya, P.C.; Wayland, J.R. Jr.

    1984-03-30

    A method for enhancing the resistivity contrasts of a thermal front in an oil recovery production field as measured by the controlled source audio frequency magnetotelluric (CSAMT) technique is disclosed. This method includes the steps of: (1) preparing a CSAMT-determined topological resistivity map of the production field; (2) introducing a solution of a dopant material into the production field at a concentration effective to alter the resistivity associated with the thermal front; said dopant material having a high cation exchange capacity which might be selected from the group consisting of montmorillonite, illite, and chlorite clays; said material being soluble in the conate water of the production field; (3) preparing a CSAMT-determined topological resistivity map of the production field while said dopant material is moving therethrough; and (4) mathematically comparing the maps from step (1) and step (3) to determine the location of the thermal front. This method is effective with the steam flood, fire flood and water flood techniques.

  9. Methods for enhancing mapping of thermal fronts in oil recovery

    DOE Patents [OSTI]

    Lee, David O.; Montoya, Paul C.; Wayland, Jr., James R.

    1987-01-01

    A method for enhancing the resistivity contrasts of a thermal front in an oil recovery production field as measured by the CSAMT technique is disclosed. This method includes the steps of: (a) preparing a CSAMT-determined topological resistivity map of the production field; (b) introducing a solution of a dopant material into the production field at a concentration effective to alter the resistivity associated with the thermal front; said dopant material having a high cation exchange capacity which might be selected from the group consisting of montmorillonite, illite, and chlorite clays; said material being soluble in the connate water of the production field; (c) preparing a CSAMT-determined topological resistivity map of the production field while said dopant material is moving therethrough; and (d) mathematically comparing the maps from step (a) and step (c) to determine the location of the thermal front. This method is effective with the steam flood, fire flood and water flood techniques.

  10. Reexamination of Basal Plane Thermal Conductivity of Suspended Graphene Samples Measured by Electro-Thermal Micro-Bridge Methods

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Jo, Insun; Pettes, Michael; Lindsay, Lucas R.; Ou, Eric; Weathers, Annie; Moore, Arden; Yao, Zhen; Shi, Li

    2015-05-18

    Thermal transport in suspended graphene samples has been measured in prior works and this work with the use of a suspended electro-thermal micro-bridge method. These measurement results are analyzed here to evaluate and eliminate the errors caused by the extrinsic thermal contact resistance. It is noted that the thermal resistance measured in a recent work increases linearly with the suspended length of the single-layer graphene samples synthesized by chemical vapor deposition (CVD), and that such a feature does not reveal the failure of Fourier s law despite the increase in the apparent thermal conductivity with length. The re-analyzed thermal conductivitymore » of a single-layer CVD graphene sample reaches about ( 1680 180 )Wm-1K-1 at room temperature, which is close to the highest value reported for highly oriented pyrolytic graphite. In comparison, the thermal conductivity values measured for two suspended exfoliated bi-layer graphene samples are about ( 880 60 ) and ( 730 60 ) Wm-1K-1 at room temperature, and approach that of the natural graphite source above room temperature. However, the low-temperature thermal conductivities of these suspended graphene samples are still considerably lower than the graphite values, with the peak thermal conductivities shifted to much higher temperatures. Analysis of the thermal conductivity data reveals that the low temperature behavior is dominated by phonon scattering by polymer residue instead of by the lateral boundary.« less

  11. Reexamination of Basal Plane Thermal Conductivity of Suspended Graphene Samples Measured by Electro-Thermal Micro-Bridge Methods

    SciTech Connect (OSTI)

    Jo, Insun; Pettes, Michael; Lindsay, Lucas R; Ou, Eric; Weathers, Annie; Moore, Arden; Yao, Zhen; Shi, Li

    2015-01-01

    Thermal transport in suspended graphene samples has been measured in prior works and this work with the use of a suspended electro-thermal micro-bridge method. These measurement results are analyzed here to evaluate and eliminate the errors caused by the extrinsic thermal contact resistance. It is noted that the thermal resistance measured in a recent work increases linearly with the suspended length of the single-layer graphene samples synthesized by chemical vapor deposition (CVD), and that such a feature does not reveal the failure of Fourier s law despite the increase in the apparent thermal conductivity with length. The re-analyzed thermal conductivity of a single-layer CVD graphene sample reaches about ( 1680 180 )Wm-1K-1 at room temperature, which is close to the highest value reported for highly oriented pyrolytic graphite. In comparison, the thermal conductivity values measured for two suspended exfoliated bi-layer graphene samples are about ( 880 60 ) and ( 730 60 ) Wm-1K-1 at room temperature, and approach that of the natural graphite source above room temperature. However, the low-temperature thermal conductivities of these suspended graphene samples are still considerably lower than the graphite values, with the peak thermal conductivities shifted to much higher temperatures. Analysis of the thermal conductivity data reveals that the low temperature behavior is dominated by phonon scattering by polymer residue instead of by the lateral boundary.

  12. Investigation of Thermal Interface Materials Using Phase-Sensitive Transient Thermoreflectance Technique: Preprint

    SciTech Connect (OSTI)

    Feng, X.; King, C.; DeVoto, D.; Mihalic, M.; Narumanchi, S.

    2014-08-01

    With increasing power density in electronics packages/modules, thermal resistances at multiple interfaces are a bottleneck to efficient heat removal from the package. In this work, the performance of thermal interface materials such as grease, thermoplastic adhesives and diffusion-bonded interfaces are characterized using the phase-sensitive transient thermoreflectance technique. A multi-layer heat conduction model was constructed and theoretical solutions were derived to obtain the relation between phase lag and the thermal/physical properties. This technique enables simultaneous extraction of the contact resistance and bulk thermal conductivity of the TIMs. With the measurements, the bulk thermal conductivity of Dow TC-5022 thermal grease (70 to 75 um bondline thickness) was 3 to 5 W/(m-K) and the contact resistance was 5 to 10 mm2-K/W. For the Btech thermoplastic material (45 to 80 μm bondline thickness), the bulk thermal conductivity was 20 to 50 W/(m-K) and the contact resistance was 2 to 5 mm2-K/W. Measurements were also conducted to quantify the thermal performance of diffusion-bonded interface for power electronics applications. Results with the diffusion-bonded sample showed that the interfacial thermal resistance is more than one order of magnitude lower than those of traditional TIMs, suggesting potential pathways to efficient thermal management.

  13. 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))

    1994-03-01

    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.

  14. Reducing Thermal Losses and Gains With Buried and Encapsulated Ducts in Hot-Humid Climates

    SciTech Connect (OSTI)

    Shapiro, C.; Magee, A.; Zoeller, W.

    2013-02-01

    The Consortium for Advanced Residential Buildings (CARB) monitored three houses in Jacksonville, FL, to investigate the effectiveness of encapsulated and encapsulated/buried ducts in reducing thermal losses and gains from ductwork in unconditioned attics. Burying ductwork beneath loose-fill insulation has been identified as an effective method of reducing thermal losses and gains from ductwork in dry climates, but it is not applicable in humid climates where condensation may occur on the outside of the duct jacket. By encapsulating the ductwork in closed cell polyurethane foam (ccSPF) before burial beneath loose-fill mineral fiber insulation, the condensation potential may be reduced while increasing the R-value of the ductwork.

  15. THERMAL CONDUCTIVITY AND OTHER PROPERTIES OF CEMENTITIOUS GROUTS

    SciTech Connect (OSTI)

    ALLAN,M.

    1998-05-01

    The thermal conductivity and other properties cementitious grouts have been investigated in order to determine suitability of these materials for grouting vertical boreholes used with geothermal heat pumps. The roles of mix variables such as water/cement ratio, sand/cement ratio and superplasticizer dosage were measured. In addition to thermal conductivity, the cementitious grouts were also tested for bleeding, permeability, bond to HDPE pipe, shrinkage, coefficient of thermal expansion, exotherm, durability and environmental impact. This paper summarizes the results for selected grout mixes. Relatively high thermal conductivities were obtained and this leads to reduction in predicted bore length and installation costs. Improvements in shrinkage resistance and bonding were achieved.

  16. HEATS: Thermal Energy Storage

    SciTech Connect (OSTI)

    2012-01-01

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

  17. Thermal Energy Storage

    SciTech Connect (OSTI)

    Rutberg, Michael; Hastbacka, Mildred; Cooperman, Alissa; Bouza, Antonio

    2013-06-05

    The article discusses thermal energy storage technologies. This article addresses benefits of TES at both the building site and the electricity generation source. The energy savings and market potential of thermal energy store are reviewed as well.

  18. thermal energy power conversion

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

    National Solar Thermal Test Facility Nuclear ... Climate & Earth Systems Climate Measurement & Modeling ... Tribal Energy Program Intellectual Property Current EC ...

  19. Thermal neutron detection system

    DOE Patents [OSTI]

    Peurrung, Anthony J. (Richland, WA); Stromswold, David C. (West Richland, WA)

    2000-01-01

    According to the present invention, a system for measuring a thermal neutron emission from a neutron source, has a reflector/moderator proximate the neutron source that reflects and moderates neutrons from the neutron source. The reflector/moderator further directs thermal neutrons toward an unmoderated thermal neutron detector.

  20. Thermal Performance Benchmarking (Presentation)

    SciTech Connect (OSTI)

    Moreno, G.

    2014-11-01

    This project will benchmark the thermal characteristics of automotive power electronics and electric motor thermal management systems. Recent vehicle systems will be benchmarked to establish baseline metrics, evaluate advantages and disadvantages of different thermal management systems, and identify areas of improvement to advance the state-of-the-art.

  1. Solar Thermal Collector Manufacturing Activities

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

    4 Average thermal performance rating of solar thermal collectors by type shipped in 2009 ... Administration, Form EIA-63A, "Annual Solar Thermal Collector Manufacturers Survey." ...

  2. Resistance after firing protected electric match

    DOE Patents [OSTI]

    Montoya, Arsenio P.

    1981-11-10

    An electric match having electrical leads embedded in flame-producing compound is protected against an accidental resistance across the leads after firing by a length of heat-shrinkable tubing encircling the match body and having a skirt portion extending beyond the leads. The heat of the burning match and an adjacent thermal battery causes the tubing to fold over the end of the match body, covering the ends of the leads and protecting them from molten pieces of the battery.

  3. Resistance after firing protected electric match

    SciTech Connect (OSTI)

    Montoya, A.P.

    1981-11-10

    An electric match having electrical leads embedded in flameproducing compound is protected against an accidental resistance across the leads after firing by a length of heat-shrinkable tubing encircling the match body and having a skirt portion extending beyond the leads. The heat of the burning match and an adjacent thermal battery causes the tubing to fold over the end of the match body, covering the ends of the leads and protecting them from molten pieces of the battery.

  4. Characterization of Contact and Bulk Thermal Resistance of Laminations...

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

    ... References 1 Bennion, K., and Cousineau, J., "Sensitivity Analysis of Traction Drive Motor Cooling." Paper presented at the IEEE Transportation Electrification Conference and ...

  5. High strength, thermally stable, oxidation resistant, nickel-based alloy

    DOE Patents [OSTI]

    Sikka, Vinod K.; Deevi, Seetharama C.; Vought, Joseph D.; Howell, C. Randal

    1999-01-01

    A polycrystalline alloy is composed essentially of, by weight %: 15% to 30% Mo, 3% to 10% Al, up to 10% Cr, up to 10% Fe, up to 2% Si, 0.01% to 0.2% C, 0.01% to 0.04% B, balance Ni.

  6. Weather-Resistive Barriers

    SciTech Connect (OSTI)

    2000-10-01

    How to select and install housewrap and other types of weather-resistive barriers: Building Technology Fact Sheet

  7. Thermal Effusivity Tomography from Pulsed Thermal Imaging

    Energy Science and Technology Software Center (OSTI)

    2006-12-01

    The software program generates 3D volume distribution of thermal effusivity within a test material from one-sided pulsed thermal imaging data. Thsi is the first software capable of accurate, fast and automated thermal tomographic imaging of inhomogeneous materials to produce 3D images similar to those obtained from 3D X-ray CT (all previous thermal-imaging software can only produce 2D results). Because thermal effusivity is an intrisic material property that is related to material constituent, density, conductivity, etc.,more » quantitative imaging of effusivity allowed direct visualization of material's internal constituent/structure and damage distributions, thereby potentially leading to quantitative prediction of other material properties such as strength. I can be therefre be used for 3D imaging of material structure in fundamental material studies, nondestructive characterization of defects/flaws in structural engineering components, health monitoring of material damage and degradation during service, and medical imaging and diagnostics. This technology is one-sided, non contact and sensitive to material's thermal property and discontinuity. One major advantage of this tomographic technology over x-ray CT and ultrasounds is its natural efficiency for 3D imaging of the volume under a large surface area. This software is implemented with a method for thermal computed tomography of thermal effusivity from one-sided pulsed thermal imaging (or thermography) data. The method is based on several solutions of the governing heat transfer equation under pulsed thermography test condition. In particular, it consists of three components. 1) It utilized the thermal effusivity as the imaging parameter to construct the 3D image. 2) It established a relationship between the space (depth) and the time, because thermography data are in the time domain. 3) It incorporated a deconvolution algorithm to solve the depth porfile of the material thermal effusivity from the measured

  8. Radiation coloration resistant glass

    DOE Patents [OSTI]

    Tomozawa, M.; Watson, E.B.; Acocella, J.

    1986-11-04

    A radiation coloration resistant glass is disclosed which is used in a radiation environment sufficient to cause coloration in most forms of glass. The coloration resistant glass includes higher proportions by weight of water and has been found to be extremely resistant to color change when exposed to such radiation levels. The coloration resistant glass is free of cerium oxide and has more than about 0.5% by weight water content. Even when exposed to gamma radiation of more than 10[sup 7] rad, the coloration resistant glass does not lose transparency. 3 figs.

  9. Radiation coloration resistant glass

    DOE Patents [OSTI]

    Tomozawa, Minoru; Watson, E. Bruce; Acocella, John

    1986-01-01

    A radiation coloration resistant glass is disclosed which is used in a radiation environment sufficient to cause coloration in most forms of glass. The coloration resistant glass includes higher proportions by weight of water and has been found to be extremely resistant to color change when exposed to such radiation levels. The coloration resistant glass is free of cerium oxide and has more than about 0.5% by weight water content. Even when exposed to gamma radiation of more than 10.sup.7 rad, the coloration resistant glass does not lose transparency.

  10. Engineered metal matrix composites for improved thermal fatigue and wear

    SciTech Connect (OSTI)

    Runkle, J.C.

    1996-12-31

    A new class of patented, steel/carbide metal matrix composites, engineered and developed by UltraClad Corporation, has been applied in concert with HIP cladding to solve several specific real world manufacturing problems, including: improved thermal fatigue performance and wear resistance of metal hot working rolls and related tooling; and improved resistance of tooling to attack by molten aluminum. The thought, science, and engineering behind the evolution and development of these products will be reviewed.

  11. Thermal Effusivity Tomography from Pulsed Thermal Imaging

    Energy Science and Technology Software Center (OSTI)

    2008-11-05

    The software program generates 3D volume distribution of thermal effusivity within a test material from one—sided pulsed thermal imaging data. Thsi is the first software capable of accurate, fast and automated thermal tomographic imaging of inhomogeneoirs materials to produce 3D images similar to those obtained from 3D X—ray CT (all previous thepnal—imaging software can only produce 20 results) . Because thermal effusivity is an Intrisic material property that is related to material constituent, density, conductivity,more » etc., quantitative imaging of eftusivity allowed direct visualization of material’s internal constituent/structure and damage distributions, thereby potentially leading to quantitative prediction of other material properties such as strength. I can be therefre be used for 3D imaging of material structure in fundamental material studies, nondestructive characterization of defects/flaws in structural engineering components, health monitoring of material damage and degradation during service, and medical imaging and diagnostics. This technology is one—sided, non contact and sensitive to material’s thermal property and discontinuity. One major advantage of this tomographic technology over x-ray CT and ultrasounds is its natural efficiency for 3D imaging of the volume under a large surface area. This software is implemented with a method for thermal computed tomography of thermal effusivity from one—sided pulsed thermal imaging (or thermography) data. The method is based on several solutions of the governing heat transfer equation under pulsed thermography test condition. In particular, it consists of three components. 1) It utilized the thermal effusivity as the imaging parameter to construct the 3D image. 2) It established a relationship between the space (depth) and the time, because thermography data are in the time domain. 3) It incorporated a deconvolution algorithm to solve the depth porfile of the material thermal effusivity from the

  12. Catalytic thermal barrier coatings

    DOE Patents [OSTI]

    Kulkarni, Anand A.; Campbell, Christian X.; Subramanian, Ramesh

    2009-06-02

    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.

  13. Solid state thermal rectifier

    DOE Patents [OSTI]

    None

    2016-07-05

    Thermal rectifiers using linear nanostructures as core thermal conductors have been fabricated. A high mass density material is added preferentially to one end of the nanostructures to produce an axially non-uniform mass distribution. The resulting nanoscale system conducts heat asymmetrically with greatest heat flow in the direction of decreasing mass density. Thermal rectification has been demonstrated for linear nanostructures that are electrical insulators, such as boron nitride nanotubes, and for nanostructures that are conductive, such as carbon nanotubes.

  14. Sandia Thermal Program

    Energy Science and Technology Software Center (OSTI)

    2005-11-23

    Thermal analysis in 1-D planar, cylindrical and spherical geometries using control volume finite element spatial discretization with 1st and 2nd order implicit time integrators.

  15. Scattering Solar Thermal Concentrators

    Office of Environmental Management (EM)

    sunshot DOEGO-102012-3669 * September 2012 MOTIVATION All thermal concentrating solar power (CSP) systems use solar tracking, which involves moving large mirror surfaces...

  16. Battery Thermal Characterization

    SciTech Connect (OSTI)

    Saxon, Aron; Powell, Mitchell; Shi, Ying

    2015-06-09

    This presentation provides an update of NREL's battery thermal characterization efforts for the 2015 U.S. Department of Energy Annual Merit Reviews.

  17. Ambient temperature thermal battery

    SciTech Connect (OSTI)

    Fletcher, A. N.; Bliss, D. E.; McManis III

    1985-11-26

    An ambient temperature thermal battery having two relatively high temperature melting electrolytes which form a low melting temperature electrolyte upon activation.

  18. Note: A simple model for thermal management in solenoids

    SciTech Connect (OSTI)

    McIntosh, E. M. Ellis, J.

    2013-11-15

    We describe a model of the dynamical temperature evolution in a solenoid winding. A simple finite element analysis is calibrated by accurately measuring the thermally induced resistance change of the solenoid, thus obviating the need for accurate knowledge of the mean thermal conductivity of the windings. The model predicts quasi thermal runaway for relatively modest current increases from the normal operating conditions. We demonstrate the application of this model to determine the maximum current that can be safely applied to solenoids used for helium spin-echo measurements.

  19. Resistive-ideal

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

    Resistive-ideal transition of pressure-driven instabilities in current-carrying plasmas beyond the Suydam criterion F. Ebrahimi, S. C. Prager, and C. R. Sovinec University of Wisconsin-Madison, Madison, Wisconsin 53706 ͑Received 14 January 2002; accepted 8 April 2002͒ The linear magnetohydrodynamics stability of local and global resistive pressure-driven instabilities is examined computationally in a cylinder. Both instabilities are resistive from beta values of zero up to several times the

  20. Hydrogen permeation resistant barrier

    DOE Patents [OSTI]

    McGuire, J.C.; Brehm, W.F.

    1980-02-08

    A hydrogen permeation resistant barrier is formed by diffusing aluminum into an iron or nickel alloy and forming an intermetallic aluminide layer.

  1. Hydrogen permeation resistant barrier

    DOE Patents [OSTI]

    McGuire, Joseph C.; Brehm, William F.

    1982-01-01

    A hydrogen permeation resistant barrier is formed by diffusing aluminum into an iron or nickel alloy and forming an intermetallic aluminide layer.

  2. Variable pressure thermal insulating jacket

    DOE Patents [OSTI]

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

    1994-09-20

    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.

  3. Variable pressure thermal insulating jacket

    DOE Patents [OSTI]

    Nelson, Paul A. (Wheaton, IL); Malecha, Richard F. (Naperville, IL); Chilenskas, Albert A. (Chicago, IL)

    1994-01-01

    A device for controlled insulation of a thermal device. 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 communcation 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.

  4. Effect of air movement on thermal resistance of loose-fill thermal insulations

    SciTech Connect (OSTI)

    Yarbrough, D.W.; Toor, I.A.

    1981-12-01

    An apparatus to measure the heat flux through horizontally applied loosefill insulations with air movement above the insulation has been constructed and used to test specimens of loose-fill cellulosic, fiberglass, and rock wool insulations. Heat flux divided by the temperature difference across insulation specimens was measured for air velocities up to 92 cm/s. An increase in the heat flux term with air movement was observed and correlated with air velocity and specimen density. The magnitude of the increase in the heat flux term was greatest for the specimen of low-density fiberglass insulation.

  5. Effect of air movement on thermal resistance of loose-fill thermal insulations

    SciTech Connect (OSTI)

    Yarbrough, D.W.; Toor, I.A.

    1983-01-01

    An apparatus to measure the heat flux through horizontally applied loose-fill insulations with air movement above the insulation has been constructed and used to test specimens of loose-fill cellulosic, fiberglass, and rock wool insulations. Heat flux divided by the temperature difference across insulation specimens was measured for air velocities up to 92 cm/s. An increase in the heat flux term with air movement was observed and correlated with air velocity and specimen density. The magnitude of the increase in the heat flux term was greatest for the specimen of low-density fiberglass insulation.

  6. Thermal protection apparatus

    DOE Patents [OSTI]

    Bennett, G.A.; Elder, M.G.; Kemme, J.E.

    1984-03-20

    The disclosure is directed to an apparatus for thermally protecting sensitive components in tools used in a geothermal borehole. The apparatus comprises a Dewar within a housing. The Dewar contains heat pipes such as brass heat pipes for thermally conducting heat from heat sensitive components such as electronics to a heat sink such as ice.

  7. Thermal protection apparatus

    DOE Patents [OSTI]

    Bennett, Gloria A.; Elder, Michael G.; Kemme, Joseph E.

    1985-01-01

    An apparatus which thermally protects sensitive components in tools used in a geothermal borehole. The apparatus comprises a Dewar within a housing. The Dewar contains heat pipes such as brass heat pipes for thermally conducting heat from heat sensitive components to a heat sink such as ice.

  8. Thermally actuated wedge block

    DOE Patents [OSTI]

    Queen, Jr., Charles C.

    1980-01-01

    This invention relates to an automatically-operating wedge block for maintaining intimate structural contact over wide temperature ranges, including cryogenic use. The wedging action depends on the relative thermal expansion of two materials having very different coefficients of thermal expansion. The wedge block expands in thickness when cooled to cryogenic temperatures and contracts in thickness when returned to room temperature.

  9. Tunable thermal link

    DOE Patents [OSTI]

    Chang, Chih-Wei; Majumdar, Arunava; Zettl, Alexander K.

    2014-07-15

    Disclosed is a device whereby the thermal conductance of a multiwalled nanostructure such as a multiwalled carbon nanotube (MWCNT) can be controllably and reversibly tuned by sliding one or more outer shells with respect to the inner core. As one example, the thermal conductance of an MWCNT dropped to 15% of the original value after extending the length of the MWCNT by 190 nm. The thermal conductivity returned when the tube was contracted. The device may comprise numbers of multiwalled nanotubes or other graphitic layers connected to a heat source and a heat drain and various means for tuning the overall thermal conductance for applications in structure heat management, heat flow in nanoscale or microscale devices and thermal logic devices.

  10. Thermal treatment wall

    DOE Patents [OSTI]

    Aines, Roger D.; Newmark, Robin L.; Knauss, Kevin G.

    2000-01-01

    A thermal treatment wall emplaced to perform in-situ destruction of contaminants in groundwater. Thermal destruction of specific contaminants occurs by hydrous pyrolysis/oxidation at temperatures achievable by existing thermal remediation techniques (electrical heating or steam injection) in the presence of oxygen or soil mineral oxidants, such as MnO.sub.2. The thermal treatment wall can be installed in a variety of configurations depending on the specific objectives, and can be used for groundwater cleanup, wherein in-situ destruction of contaminants is carried out rather than extracting contaminated fluids to the surface, where they are to be cleaned. In addition, the thermal treatment wall can be used for both plume interdiction and near-wellhead in-situ groundwater treatment. Thus, this technique can be utilized for a variety of groundwater contamination problems.

  11. Solar thermal aircraft

    DOE Patents [OSTI]

    Bennett, Charles L.

    2007-09-18

    A solar thermal powered aircraft powered by heat energy from the sun. A heat engine, such as a Stirling engine, is carried by the aircraft body for producing power for a propulsion mechanism, such as a propeller. The heat engine has a thermal battery in thermal contact with it so that heat is supplied from the thermal battery. A solar concentrator, such as reflective parabolic trough, is movably connected to an optically transparent section of the aircraft body for receiving and concentrating solar energy from within the aircraft. Concentrated solar energy is collected by a heat collection and transport conduit, and heat transported to the thermal battery. A solar tracker includes a heliostat for determining optimal alignment with the sun, and a drive motor actuating the solar concentrator into optimal alignment with the sun based on a determination by the heliostat.

  12. Crack-resistant siloxane molding compounds. [Patent application

    DOE Patents [OSTI]

    McFarland, J.W.; Swearngin, C.B.

    1980-11-03

    The crack resistance of phenyl silicone molding resins containing siliceous fillers is improved by incorporating therein about 0.5 to 5.5% by weight of ..beta..-eucryptite, a lithium aluminum silicate having a negative thermal expansion coefficient. These molding resins are particularly suitable for encapsulating electronic devices such as diodes, coils, resistors, and the like.

  13. High temperature, low expansion, corrosion resistant ceramic and gas turbine

    DOE Patents [OSTI]

    Rauch, Sr., Harry W.

    1981-01-01

    The present invention relates to ZrO.sub.2 -MgO-Al.sub.2 O.sub.3 -SiO.sub.2 ceramic materials having improved thermal stability and corrosion resistant properties. The utilization of these ceramic materials as heat exchangers for gas turbine engines is also disclosed.

  14. Method for transferring thermal energy and electrical current in thin-film electrochemical cells

    DOE Patents [OSTI]

    Rouillard, Roger; Domroese, Michael K.; Hoffman, Joseph A.; Lindeman, David D.; Noel, Joseph-Robert-Gaetan; Radewald, Vern E.; Ranger, Michel; Sudano, Anthony; Trice, Jennifer L.; Turgeon, Thomas A.

    2003-05-27

    An improved electrochemical generator is disclosed. The electrochemical generator includes a thin-film electrochemical cell which is maintained in a state of compression through use of an internal or an external pressure apparatus. A thermal conductor, which is connected to at least one of the positive or negative contacts of the cell, conducts current into and out of the cell and also conducts thermal energy between the cell and thermally conductive, electrically resistive material disposed on a vessel wall adjacent the conductor. The thermally conductive, electrically resistive material may include an anodized coating or a thin sheet of a plastic, mineral-based material or conductive polymer material. The thermal conductor is fabricated to include a resilient portion which expands and contracts to maintain mechanical contact between the cell and the thermally conductive material in the presence of relative movement between the cell and the wall structure. The electrochemical generator may be disposed in a hermetically sealed housing.

  15. Thermally-related safety issues associated with thermal batteries.

    SciTech Connect (OSTI)

    Guidotti, Ronald Armand

    2006-06-01

    Thermal batteries can experience thermal runaway under certain usage conditions. This can lead to safety issues for personnel and cause damage to associated test equipment if the battery thermally self destructs. This report discusses a number of thermal and design related issues that can lead to catastrophic destruction of thermal batteries under certain conditions. Contributing factors are identified and mitigating actions are presented to minimize or prevent undesirable thermal runaway.

  16. Low Thermal Conductivity, High Durability Thermal Barrier Coatings for IGCC Environments

    SciTech Connect (OSTI)

    Jordan, Eric; Gell, Maurice

    2015-01-15

    Advanced thermal barrier coatings (TBC) are crucial to improved energy efficiency in next generation gas turbine engines. The use of traditional topcoat materials, e.g. yttria-stabilized zirconia (YSZ), is limited at elevated temperatures due to (1) the accelerated undesirable phase transformations and (2) corrosive attacks by calcium-magnesium-aluminum-silicate (CMAS) deposits and moisture. The first goal of this project is to use the Solution Precursor Plasma Spray (SPPS) process to further reduce the thermal conductivity of YSZ TBCs by introducing a unique microstructural feature of layered porosity, called inter-pass boundaries (IPBs). Extensive process optimization accompanied with hundreds of spray trials as well as associated SEM cross-section and laser-flash measurements, yielded a thermal conductivity as low as 0.62 Wm⁻¹K⁻¹ in SPPS YSZ TBCs, approximately 50% reduction of APS TBCs; while other engine critical properties, such as cyclic durability, erosion resistance and sintering resistance, were characterized to be equivalent or better than APS baselines. In addition, modifications were introduced to SPPS TBCs so as to enhance their resistance to CMAS under harsh IGCC environments. Several mitigation approaches were explored, including doping the coatings with Al₂O₃ and TiO₂, applying a CMAS infiltration-inhibiting surface layer, and filling topcoat cracks with blocking substances. The efficacy of all these modifications was assessed with a set of novel CMAS-TBC interaction tests, and the moisture resistance was tested in a custom-built high-temperature moisture rig. In the end, the optimal low thermal conductivity TBC system was selected based on all evaluation tests and its processing conditions were documented. The optimal coating consisted on a thick inner layer of YSZ coating made by the SPPS process having a thermal conductivity 50% lower than standard YSZ coatings topped with a high temperature tolerant CMAS resistant gadolinium

  17. AC resistance measuring instrument

    DOE Patents [OSTI]

    Hof, P.J.

    1983-10-04

    An auto-ranging AC resistance measuring instrument for remote measurement of the resistance of an electrical device or circuit connected to the instrument includes a signal generator which generates an AC excitation signal for application to a load, including the device and the transmission line, a monitoring circuit which provides a digitally encoded signal representing the voltage across the load, and a microprocessor which operates under program control to provide an auto-ranging function by which range resistance is connected in circuit with the load to limit the load voltage to an acceptable range for the instrument, and an auto-compensating function by which compensating capacitance is connected in shunt with the range resistance to compensate for the effects of line capacitance. After the auto-ranging and auto-compensation functions are complete, the microprocessor calculates the resistance of the load from the selected range resistance, the excitation signal, and the load voltage signal, and displays of the measured resistance on a digital display of the instrument. 8 figs.

  18. AC Resistance measuring instrument

    DOE Patents [OSTI]

    Hof, Peter J.

    1983-01-01

    An auto-ranging AC resistance measuring instrument for remote measurement of the resistance of an electrical device or circuit connected to the instrument includes a signal generator which generates an AC excitation signal for application to a load, including the device and the transmission line, a monitoring circuit which provides a digitally encoded signal representing the voltage across the load, and a microprocessor which operates under program control to provide an auto-ranging function by which range resistance is connected in circuit with the load to limit the load voltage to an acceptable range for the instrument, and an auto-compensating function by which compensating capacitance is connected in shunt with the range resistance to compensate for the effects of line capacitance. After the auto-ranging and auto-compensation functions are complete, the microprocessor calculates the resistance of the load from the selected range resistance, the excitation signal, and the load voltage signal, and displays of the measured resistance on a digital display of the instrument.

  19. Multilayer thermal barrier coating systems

    DOE Patents [OSTI]

    Vance, Steven J.; Goedjen, John G.; Sabol, Stephen M.; Sloan, Kelly M.

    2000-01-01

    The present invention generally describes multilayer thermal barrier coating systems and methods of making the multilayer thermal barrier coating systems. The thermal barrier coating systems comprise a first ceramic layer, a second ceramic layer, a thermally grown oxide layer, a metallic bond coating layer and a substrate. The thermal barrier coating systems have improved high temperature thermal and chemical stability for use in gas turbine applications.

  20. Induced natural convection thermal cycling device

    DOE Patents [OSTI]

    Heung, Leung Kit

    2002-08-13

    A device for separating gases, especially isotopes, by thermal cycling of a separation column using a pressure vessel mounted vertically and having baffled sources for cold and heat. Coils at the top are cooled with a fluid such as liquid nitrogen. Coils at the bottom are either electrical resistance coils or a tubular heat exchange. The sources are shrouded with an insulated "top hat" and simultaneously opened and closed at the outlets to cool or heat the separation column. Alternatively, the sources for cold and heat are mounted separately outside the vessel and an external loop is provided for each circuit.

  1. Solar Thermal Collector Manufacturing Activities

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

    2 Solar thermal collector shipments by type, quantity, revenue, and average price, 2008 ... Source: U.S. Energy Information Administration, Form EIA-63A, "Annual Solar Thermal ...

  2. Solar Thermal Collector Manufacturing Activities

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

    1 Distribution of domestic solar thermal collector shipments (thousand square feet) 2008 ... Source: U.S. Energy Information Administration, Form EIA-63A, "Annual Solar Thermal ...

  3. Solar Thermal Collector Manufacturing Activities

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

    Annual shipments of solar thermal collectors by type, 2000 - 2009 (thousand square feet) ... Source: U.S. Energy Information Administration, Form EIA-63A, "Annual Solar Thermal ...

  4. Solar Thermal Collector Manufacturing Activities

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

    Shipments of solar thermal collectors ranked by origin and destination, 2009 Origin Top ... Source: U.S. Energy Information Administration, Form EIA-63A, "Annual Solar Thermal ...

  5. Solar Thermal Collector Manufacturing Activities

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

    Annual shipments of solar thermal collectors by source, 2000 - 2009 Imports Domestically ... Source: U.S. Energy Information Administration, Form EIA-63A, "Annual Solar Thermal ...

  6. Solar Thermal Collector Manufacturing Activities

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

    Annual shipments of solar thermal collectors by disposition, 2000 - 2009 (thousand square ... Source: U.S. Energy Information Administration, Form EIA-63A, "Annual Solar Thermal ...

  7. Solar Thermal Collector Manufacturing Activities

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

    7 Percent of solar thermal collector shipments by the 10 largest companies, 2000 - 2009 ... Source: U.S. Energy Information Administration, Form EIA-63A, "Annual Solar Thermal ...

  8. Solar Thermal Collector Manufacturing Activities

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

    5 Shipments of complete solar thermal collector systems, 2008 and 2009 Shipment ... Administration, Form EIA-63A, "Annual Solar Thermal Collector Manufacturers Survey."

  9. Solar Thermal Collector Manufacturing Activities

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

    8 Import shipments of solar thermal collectors by country, 2008 and 2009 (square feet) ... Source: U.S. Energy Information Administration, Form EIA-63A, "Annual Solar Thermal ...

  10. Solar Thermal Collector Manufacturing Activities

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

    7 Import shipments of solar thermal collectors by type, 2000 - 2009 (thousand square feet) ... Source: U.S. Energy Information Administration, Form EIA-63A, "Annual Solar Thermal ...

  11. Thermal insulations using vacuum panels

    DOE Patents [OSTI]

    Glicksman, Leon R.; Burke, Melissa S.

    1991-07-16

    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.

  12. National Solar Thermal Test Facility

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

    National Solar Thermal Test Facility HomeNational Solar Thermal Test Facility Permalink Pratt Whitney Rocketdyne Testing Concentrating Solar Power, EC, Energy, Facilities, ...

  13. National Solar Thermal Test Facility

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

    SunShot Grand Challenge: Regional Test Centers National Solar Thermal Test Facility HomeTag:National Solar Thermal Test Facility Permalink Air Force Research Laboratory Testing ...

  14. National Solar Thermal Test Facility

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

    National Solar Thermal Test Facility HomeNational Solar Thermal Test Facility Permalink High-Efficiency Solar Thermochemical Reactor for Hydrogen Production Center for ...

  15. Thermal Properties Measurement Report

    SciTech Connect (OSTI)

    Carmack, Jon; Braase, Lori; Papesch, Cynthia; Hurley, David; Tonks, Michael; Zhang, Yongfeng; Gofryk, Krzysztof; Harp, Jason; Fielding, Randy; Knight, Collin; Meyer, Mitch

    2015-08-01

    The Thermal Properties Measurement Report summarizes the research, development, installation, and initial use of significant experimental thermal property characterization capabilities at the INL in FY 2015. These new capabilities were used to characterize a U3Si2 (candidate Accident Tolerant) fuel sample fabricated at the INL. The ability to perform measurements at various length scales is important and provides additional data that is not currently in the literature. However, the real value of the data will be in accomplishing a phenomenological understanding of the thermal conductivity in fuels and the ties to predictive modeling. Thus, the MARMOT advanced modeling and simulation capability was utilized to illustrate how the microstructural data can be modeled and compared with bulk characterization data. A scientific method was established for thermal property measurement capability on irradiated nuclear fuel samples, which will be installed in the Irradiated Material Characterization Laboratory (IMCL).

  16. Radiation resistant austenitic stainless steel alloys

    DOE Patents [OSTI]

    Maziasz, Philip J.; Braski, David N.; Rowcliffe, Arthur F.

    1989-01-01

    An austenitic stainless steel alloy, with improved resistance to radiation-induced swelling and helium embrittlement, and improved resistance to thermal creep at high temperatures, consisting essentially of, by weight percent: from 16 to 18% nickel; from 13 to 17% chromium; from 2 to 3% molybdenum; from 1.5 to 2.5% manganese; from 0.01 to 0.5% silicon; from 0.2 to 0.4% titanium; from 0.1 to 0.2% niobium; from 0.1 to 0.6% vanadium; from 0.06 to 0.12% carbon; from 0.01% to 0.03% nitrogen; from 0.03 to 0.08% phosphorus; from 0.005 to 0.01% boron; and the balance iron, and wherein the alloy may be thermomechanically treated to enhance physical and mechanical properties.

  17. Radiation resistant austenitic stainless steel alloys

    DOE Patents [OSTI]

    Maziasz, P.J.; Braski, D.N.; Rowcliffe, A.F.

    1987-02-11

    An austenitic stainless steel alloy, with improved resistance to radiation-induced swelling and helium embrittlement, and improved resistance to thermal creep at high temperatures, consisting essentially of, by weight percent: from 16 to 18% nickel; from 13 to 17% chromium; from 2 to 3% molybdenum; from 1.5 to 2.5% manganese; from 0.01 to 0.5% silicon; from 0.2 to 0.4% titanium; from 0.1 to 0.2% niobium; from 0.1 to 0.6% vanadium; from 0.06 to 0.12% carbon; from 0.01 to 0.03% nitrogen; from 0.03 to 0.08% phosphorus; from 0.005 to 0.01% boron; and the balance iron, and wherein the alloy may be thermomechanically treated to enhance physical and mechanical properties. 4 figs.

  18. Underhood Thermal Performance

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

    Underhood Thermal Performance This email address is being protected from spambots. You need JavaScript enabled to view it. - Computational Fluid Dynamics Project Leader Background As vehicle technology advances, automakers need a better understanding of underhood heat loads, especially as they relate to emissions and fuel efficiency. Manufacturers of heavy-duty vehicles and off-road machines have similar concerns. Ineffective underhood thermal management can lead to higher emissions, reduced

  19. Turbine Thermal Management

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

    Turbine Thermal Management Fact Sheets Research Team Members Key Contacts Turbine Thermal Management The gas turbine is the workhorse of power generation, and technology advances to current land-based turbines are directly linked to our country's economic and energy security. Technical advancement for any type of gas turbine generally implies better performance, greater efficiency, and extended component life. From the standpoint of cycle efficiency and durability, this suggests that a continual

  20. Photovoltaic-thermal collectors

    DOE Patents [OSTI]

    Cox, III, Charles H.

    1984-04-24

    A photovoltaic-thermal solar cell including a semiconductor body having antireflective top and bottom surfaces and coated on each said surface with a patterned electrode covering less than 10% of the surface area. A thermal-absorbing surface is spaced apart from the bottom surface of the semiconductor and a heat-exchange fluid is passed between the bottom surface and the heat-absorbing surface.

  1. High efficiency, oxidation resistant radio frequency susceptor

    DOE Patents [OSTI]

    Besmann, Theodore M.; Klett, James W.

    2004-10-26

    An article and method of producing an article for converting energy from one form to another having a pitch-derived graphitic foam carbon foam substrate and a single layer coating applied to all exposed surfaces wherein the coating is either silicon carbide or carbides formed from a Group IVA metal. The article is used as fully coated carbon foam susceptors that more effectively absorb radio frequency (RF) band energy and more effectively convert the RF energy into thermal band energy or sensible heat. The essentially non-permeable coatings also serve as corrosion or oxidation resistant barriers.

  2. Thermal transport across graphene and single layer hexagonal boron nitride

    SciTech Connect (OSTI)

    Zhang, Jingchao E-mail: yyue@whu.edu.cn; Hong, Yang; Yue, Yanan E-mail: yyue@whu.edu.cn

    2015-04-07

    As the dimensions of nanocircuits and nanoelectronics shrink, thermal energies are being generated in more confined spaces, making it extremely important and urgent to explore for efficient heat dissipation pathways. In this work, the phonon energy transport across graphene and hexagonal boron-nitride (h-BN) interface is studied using classic molecular dynamics simulations. Effects of temperature, interatomic bond strength, heat flux direction, and functionalization on interfacial thermal transport are investigated. It is found out that by hydrogenating graphene in the hybrid structure, the interfacial thermal resistance (R) between graphene and h-BN can be reduced by 76.3%, indicating an effective approach to manipulate the interfacial thermal transport. Improved in-plane/out-of-plane phonon couplings and broadened phonon channels are observed in the hydrogenated graphene system by analyzing its phonon power spectra. The reported R results monotonically decrease with temperature and interatomic bond strengths. No thermal rectification phenomenon is observed in this interfacial thermal transport. Results reported in this work give the fundamental knowledge on graphene and h-BN thermal transport and provide rational guidelines for next generation thermal interface material designs.

  3. Thermal conductor for high-energy electrochemical cells

    DOE Patents [OSTI]

    Hoffman, Joseph A.; Domroese, Michael K.; Lindeman, David D.; Radewald, Vern E.; Rouillard, Roger; Trice, Jennifer L.

    2000-01-01

    A thermal conductor for use with an electrochemical energy storage device is disclosed. The thermal conductor is attached to one or both of the anode and cathode contacts of an electrochemical cell. A resilient portion of the conductor varies in height or position to maintain contact between the conductor and an adjacent wall structure of a containment vessel in response to relative movement between the conductor and the wall structure. The thermal conductor conducts current into and out of the electrochemical cell and conducts thermal energy between the electrochemical cell and thermally conductive and electrically resistive material disposed between the conductor and the wall structure. The thermal conductor may be fabricated to include a resilient portion having one of a substantially C-shaped, double C-shaped, Z-shaped, V-shaped, O-shaped, S-shaped, or finger-shaped cross-section. An elastomeric spring element may be configured so as to be captured by the resilient conductor for purposes of enhancing the functionality of the thermal conductor. The spring element may include a protrusion that provides electrical insulation between the spring conductor and a spring conductor of an adjacently disposed electrochemical cell in the presence of relative movement between the cells and the wall structure. The thermal conductor may also be fabricated from a sheet of electrically conductive material and affixed to the contacts of a number of electrochemical cells.

  4. Thermal transport properties of metal/MoS{sub 2} interfaces from first principles

    SciTech Connect (OSTI)

    Mao, Rui; Kong, Byoung Don; Kim, Ki Wook, E-mail: kwk@ncsu.edu [Department of Electrical and Computer Engineering, North Carolina State University, Raleigh, North Carolina 27695-7911 (United States)

    2014-07-21

    Thermal transport properties at the metal/MoS{sub 2} interfaces are analyzed by using an atomistic phonon transport model based on the Landauer formalism and first-principles calculations. The considered structures include chemisorbed Sc(0001)/MoS{sub 2} and Ru(0001)/MoS{sub 2}, physisorbed Au(111)/MoS{sub 2}, as well as Pd(111)/MoS{sub 2} with intermediate characteristics. Calculated results illustrate a distinctive dependence of thermal transfer on the details of interfacial microstructures. More specifically, the chemisorbed case with a stronger bonding exhibits a generally smaller interfacial thermal resistance than the physisorbed. Comparison between metal/MoS{sub 2} and metal/graphene systems suggests that metal/MoS{sub 2} is significantly more resistive. Further examination of lattice dynamics identifies the presence of multiple distinct atomic planes and bonding patterns at the interface as the key origins of the observed large thermal resistance.

  5. Electric Motor Thermal Management for Electric Traction Drives (Presentation)

    SciTech Connect (OSTI)

    Bennion, K.; Cousineau, J.; Moreno, G.

    2014-09-01

    Thermal constraints place significant limitations on how electric motors ultimately perform. Finite element analysis and computational fluid dynamics modeling approaches are being increasingly utilized in the design and analysis of electric motors. As the models become more sophisticated, it is important to have detailed and accurate knowledge of material thermal properties and convective heat transfer coefficients. In this work, the thermal properties and inter-lamination thermal contact resistances were measured for different stator lamination materials. Also, convective heat transfer coefficients of automatic transmission fluid (ATF) jets were measured to better understand the heat transfer of ATF impinging on motor copper windings. Experiments were carried out at various ATF temperatures and jet velocities to quantify the influence of these parameters on heat transfer coefficients.

  6. Theoretical investigation of the impact of grain boundaries and fission gases on UO2 thermal conductivity

    SciTech Connect (OSTI)

    Du, Shiyu; Andersson, Anders D.; Germann, Timothy C.; Stanek, Christopher R.

    2012-05-02

    Thermal conductivity is one of the most important metrics of nuclear fuel performance. Therefore, it is crucial to understand the impact of microstructure features on thermal conductivity, especially since the microstructure evolves with burn-up or time in the reactor. For example, UO{sub 2} fuels are polycrystalline and for high-burnup fuels the outer parts of the pellet experience grain sub-division leading to a very fine grain structure. This is known to impact important physical properties such as thermal conductivity as fission gas release. In a previous study, we calculated the effect of different types of {Sigma}5 grain boundaries on UO{sub 2} thermal conductivity and predicted the corresponding Kapitza resistances, i.e. the resistance of the grain boundary in relation to the bulk thermal resistance. There have been reports of pseudoanisotropic effects for the thermal conductivity in cubic polycrystalline materials, as obtained from molecular dynamics simulations, which means that the conductivity appears to be a function of the crystallographic direction of the temperature gradient. However, materials with cubic symmetry should have isotropic thermal conductivity. For this reason it is necessary to determine the cause of this apparent anisotropy and in this report we investigate this effect in context of our earlier simulations of UO{sub 2} Kapitza resistances. Another source of thermal resistance comes from fission products and fission gases. Xe is the main fission gas and when generated in sufficient quantity it dissolves from the lattice and forms gas bubbles inside the crystalline structure. We have performed studies of how Xe atoms dissolved in the UO{sub 2} matrix or precipitated as bubbles impact thermal conductivity, both in bulk UO{sub 2} and in the presence of grain boundaries.

  7. Article for thermal energy storage

    DOE Patents [OSTI]

    Salyer, Ival O.

    2000-06-27

    A thermal energy storage composition is provided which is in the form of a gel. The composition includes a phase change material and silica particles, where the phase change material may comprise a linear alkyl hydrocarbon, water/urea, or water. The thermal energy storage composition has a high thermal conductivity, high thermal energy storage, and may be used in a variety of applications such as in thermal shipping containers and gel packs.

  8. Thermal insulated glazing unit

    DOE Patents [OSTI]

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

    1988-04-05

    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.

  9. Thermal insulated glazing unit

    DOE Patents [OSTI]

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

    1991-01-01

    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.

  10. Thermal trim for luminaire

    DOE Patents [OSTI]

    Bazydola, Sarah; Ghiu, Camil-Daniel; Harrison, Robert; Jeswani, Anil

    2013-11-19

    A luminaire with a thermal pathway to reduce the junction temperature of the luminaire's light source, and methods for so doing, are disclosed. The luminaire includes a can, a light engine, and a trim, that define a substantially continuous thermal pathway from the light engine to a surrounding environment. The can defines a can cavity and includes a can end region. The light engine is within the can cavity and includes a light source and a heat sink, including a heat sink end region, coupled thereto. The trim is at least partially disposed within the can cavity and includes a first trim end region coupled to the heat sink end region and a second trim end region coupled to the can end region. Thermal interface material may be located between: the heat sink and the trim, the trim and the can, and/or the heat sink and the light source.

  11. Highly directional thermal emitter

    DOE Patents [OSTI]

    Ribaudo, Troy; Shaner, Eric A; Davids, Paul; Peters, David W

    2015-03-24

    A highly directional thermal emitter device comprises a two-dimensional periodic array of heavily doped semiconductor structures on a surface of a substrate. The array provides a highly directional thermal emission at a peak wavelength between 3 and 15 microns when the array is heated. For example, highly doped silicon (HDSi) with a plasma frequency in the mid-wave infrared was used to fabricate nearly perfect absorbing two-dimensional gratings structures that function as highly directional thermal radiators. The absorption and emission characteristics of the HDSi devices possessed a high degree of angular dependence for infrared absorption in the 10-12 micron range, while maintaining high reflectivity of solar radiation (.about.64%) at large incidence angles.

  12. Thermal sprayed composite melt containment tubular component and method of making same

    DOE Patents [OSTI]

    Besser, Matthew F.; Terpstra, Robert L.; Sordelet, Daniel J.; Anderson, Iver E.

    2002-03-19

    A tubular thermal sprayed melt containment component for transient containment of molten metal or alloy wherein the tubular member includes a thermal sprayed inner melt-contacting layer for contacting molten metal or alloy to be processed, a thermal sprayed heat-generating layer deposited on the inner layer, and an optional thermal sprayed outer thermal insulating layer. The thermal sprayed heat-generating layer is inductively heated as a susceptor of an induction field or electrical resistively heated by passing electrical current therethrough. The tubular thermal sprayed melt containment component can comprise an elongated melt pour tube of a gas atomization apparatus where the melt pour tube supplies molten material from a crucible to an underlying melt atomization nozzle.

  13. Electric Motor Thermal Management R&D; NREL (National Renewable Energy Laboratory)

    SciTech Connect (OSTI)

    Bennion, Kevin

    2015-06-09

    Thermal constraints place significant limitations on how electric motors ultimately perform. Without the ability to remove heat, the motor cannot operate without sacrificing performance, efficiency, and reliability. Finite element analysis and computational fluid dynamics modeling approaches are being increasingly utilized in the design and analysis of electric motors. As the models become more sophisticated, it is important to have detailed and accurate knowledge of both the passive thermal performance and the active cooling performance. In this work, we provide an overview of research characterizing both passive and active thermal elements related to electric motor thermal management. To better characterize the passive thermal performance, work is being performed to measure motor material thermal properties and thermal contact resistances. The active cooling performance of automatic transmission fluid (ATF) jets is also being measured to better understand the heat transfer coefficients of ATF impinging on motor copper windings.

  14. Thermal ignition combustion system

    DOE Patents [OSTI]

    Kamo, R.; Kakwani, R.M.; Valdmanis, E.; Woods, M.E.

    1988-04-19

    The thermal ignition combustion system comprises means for providing walls defining an ignition chamber, the walls being made of a material having a thermal conductivity greater than 20 W/m C and a specific heat greater than 480 J/kg C with the ignition chamber being in constant communication with the main combustion chamber, means for maintaining the temperature of the walls above a threshold temperature capable of causing ignition of a fuel, and means for conducting fuel to the ignition chamber. 8 figs.

  15. Thermal ignition combustion system

    DOE Patents [OSTI]

    Kamo, Roy; Kakwani, Ramesh M.; Valdmanis, Edgars; Woods, Melvins E.

    1988-01-01

    The thermal ignition combustion system comprises means for providing walls defining an ignition chamber, the walls being made of a material having a thermal conductivity greater than 20 W/m.degree. C. and a specific heat greater than 480 J/kg.degree. C. with the ignition chamber being in constant communication with the main combustion chamber, means for maintaining the temperature of the walls above a threshold temperature capable of causing ignition of a fuel, and means for conducting fuel to the ignition chamber.

  16. Thermal Performance Benchmarking; NREL (National Renewable Energy Laboratory)

    SciTech Connect (OSTI)

    Moreno, Gilbert

    2015-06-09

    This project proposes to seek out the SOA power electronics and motor technologies to thermally benchmark their performance. The benchmarking will focus on the thermal aspects of the system. System metrics including the junction-to-coolant thermal resistance and the parasitic power consumption (i.e., coolant flow rates and pressure drop performance) of the heat exchanger will be measured. The type of heat exchanger (i.e., channel flow, brazed, folded-fin) and any enhancement features (i.e., enhanced surfaces) will be identified and evaluated to understand their effect on performance. Additionally, the thermal resistance/conductivity of the power module’s passive stack and motor’s laminations and copper winding bundles will also be measured. The research conducted will allow insight into the various cooling strategies to understand which heat exchangers are most effective in terms of thermal performance and efficiency. Modeling analysis and fluid-flow visualization may also be carried out to better understand the heat transfer and fluid dynamics of the systems.

  17. Electric Motor Thermal Management R&D (Presentation)

    SciTech Connect (OSTI)

    Bennion, K.

    2014-11-01

    Thermal constraints place significant limitations on how electric motors ultimately perform. Without the ability to remove heat, the motor cannot operate without sacrificing performance, efficiency, and reliability. Finite element analysis and computational fluid dynamics modeling approaches are being increasingly utilized in the design and analysis of electric motors. As the models become more sophisticated, it is important to have detailed and accurate knowledge of both the passive thermal performance and the active cooling performance. In this work, we provide an overview of research characterizing both passive and active thermal elements related to electric motor thermal management. To better characterize the passive thermal performance, the effective thermal properties and inter-lamination thermal contact resistances were measured for different stator lamination materials. The active cooling performance of automatic transmission fluid (ATF) jets was also measured to better understand the heat transfer coefficients of ATF impinging on motor copper windings. Ford's Mercon LV was the ATF evaluated in this study. The presentation provides an overview of prior work with a focus on describing future plans for research to be performed during FY15.

  18. Fast Resistive Bolometry

    SciTech Connect (OSTI)

    Deeney, C.; Fehl, D.L.; Hanson, D.L.; Keltner, N.R.; McGurn, J.S.; McKenney, J.L.; Spielman, R.B.

    1999-02-01

    Resistive bolometry is an accurate, robust, spectrally broadband technique for measuring absolute x-ray fluence and flux. Bolometry is an independent technique for x-ray measurements that is based on a different set of physical properties than other diagnostics such as x-ray diodes, photoconducting detectors, and P-I-N diodes. Bolometers use the temperature-driven change in element resistivity to determine the total deposited energy. The calibration of such a device is based on fundamental material properties and its physical dimensions. We describe the use of nickel and gold bolometers to measure x rays generated by high-power z pinches on Sandia's Saturn and Z accelerators. The Sandia bolometer design described herein has a pulse response of {approximately}1 ns. We describe in detail the fabrication, fielding, and data analysis issues leading to highly accurate x-ray measurements. The fundamental accuracy of resistive bolometry will be discussed.

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

    SciTech Connect (OSTI)

    Ueno, Ai; Suzuki, Yuji

    2014-03-03

    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.

  20. Research and Development for Novel Thermal Energy Storage Systems (TES) for Concentrating Solar Power (CSP)

    SciTech Connect (OSTI)

    Faghri, Amir; Bergman, Theodore L; Pitchumani, Ranga

    2013-09-26

    The overall objective was to develop innovative heat transfer devices and methodologies for novel thermal energy storage systems for concentrating solar power generation involving phase change materials (PCMs). Specific objectives included embedding thermosyphons and/or heat pipes (TS/HPs) within appropriate phase change materials to significantly reduce thermal resistances within the thermal energy storage system of a large-scale concentrating solar power plant and, in turn, improve performance of the plant. Experimental, system level and detailed comprehensive modeling approaches were taken to investigate the effect of adding TS/HPs on the performance of latent heat thermal energy storage (LHTES) systems.

  1. Thermal barrier coating

    DOE Patents [OSTI]

    Bowker, Jeffrey Charles; Sabol, Stephen M.; Goedjen, John G.

    2001-01-01

    A thermal barrier coating for hot gas path components of a combustion turbine based on a zirconia-scandia system. A layer of zirconium scandate having the hexagonal Zr.sub.3 Sc.sub.4 O.sub.12 structure is formed directly on a superalloy substrate or on a bond coat formed on the substrate.

  2. Thermal Reactor Safety

    SciTech Connect (OSTI)

    Not Available

    1980-06-01

    Information is presented concerning fire risk and protection; transient thermal-hydraulic analysis and experiments; class 9 accidents and containment; diagnostics and in-service inspection; risk and cost comparison of alternative electric energy sources; fuel behavior and experiments on core cooling in LOCAs; reactor event reporting analysis; equipment qualification; post facts analysis of the TMI-2 accident; and computational methods.

  3. Ocean thermal energy conversion

    SciTech Connect (OSTI)

    Avery, W.H.

    1983-03-17

    A brief explanation of the Ocean Thermal Energy Conversion (OTEC) concept and an estimate of the amount of energy that can be produced from the ocean resource without introducing environmental concerns are presented. Use of the OTEC system to generate electric power and products which can replace fossil fuels is shown. The OTEC program status and its prospects for the future are discussed.

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

    SciTech Connect (OSTI)

    Fuller, Thomas F.; Bandhauer, Todd; Garimella, Srinivas

    2012-01-01

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

  5. Local measurement of thermal conductivity and diffusivity

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Hurley, David H.; Schley, Robert S.; Khafizov, Marat; Wendt, Brycen L.

    2015-12-01

    Simultaneous measurement of local thermal diffusivity and conductivity is demonstrated on a range of ceramic samples. This was accomplished by measuring the temperature field spatial profile of samples excited by an amplitude modulated continuous wave laser beam. A thin gold film is applied to the samples to ensure strong optical absorption and to establish a second boundary condition that introduces an expression containing the substrate thermal conductivity. The diffusivity and conductivity are obtained by comparing the measured phase profile of the temperature field to a continuum based model. A sensitivity analysis is used to identify the optimal film thickness formore » extracting the both substrate conductivity and diffusivity. Proof of principle studies were conducted on a range of samples having thermal properties that are representative of current and advanced accident tolerant nuclear fuels. It is shown that by including the Kapitza resistance as an additional fitting parameter, the measured conductivity and diffusivity of all the samples considered agree closely with literature values. Lastly, a distinguishing feature of this technique is that it does not require a priori knowledge of the optical spot size which greatly increases measurement reliability and reproducibility.« less

  6. Local measurement of thermal conductivity and diffusivity

    SciTech Connect (OSTI)

    Hurley, David H.; Schley, Robert S.; Khafizov, Marat; Wendt, Brycen L.

    2015-12-01

    Simultaneous measurement of local thermal diffusivity and conductivity is demonstrated on a range of ceramic samples. This was accomplished by measuring the temperature field spatial profile of samples excited by an amplitude modulated continuous wave laser beam. A thin gold film is applied to the samples to ensure strong optical absorption and to establish a second boundary condition that introduces an expression containing the substrate thermal conductivity. The diffusivity and conductivity are obtained by comparing the measured phase profile of the temperature field to a continuum based model. A sensitivity analysis is used to identify the optimal film thickness for extracting the both substrate conductivity and diffusivity. Proof of principle studies were conducted on a range of samples having thermal properties that are representative of current and advanced accident tolerant nuclear fuels. It is shown that by including the Kapitza resistance as an additional fitting parameter, the measured conductivity and diffusivity of all the samples considered agree closely with literature values. Lastly, a distinguishing feature of this technique is that it does not require a priori knowledge of the optical spot size which greatly increases measurement reliability and reproducibility.

  7. Local measurement of thermal conductivity and diffusivity

    SciTech Connect (OSTI)

    Hurley, David H.; Schley, Robert S.; Khafizov, Marat; Wendt, Brycen L.

    2015-12-15

    Simultaneous measurement of local thermal diffusivity and conductivity is demonstrated on a range of ceramic samples. This was accomplished by measuring the temperature field spatial profile of samples excited by an amplitude modulated continuous wave laser beam. A thin gold film is applied to the samples to ensure strong optical absorption and to establish a second boundary condition that introduces an expression containing the substrate thermal conductivity. The diffusivity and conductivity are obtained by comparing the measured phase profile of the temperature field to a continuum based model. A sensitivity analysis is used to identify the optimal film thickness for extracting the both substrate conductivity and diffusivity. Proof of principle studies were conducted on a range of samples having thermal properties that are representatives of current and advanced accident tolerant nuclear fuels. It is shown that by including the Kapitza resistance as an additional fitting parameter, the measured conductivity and diffusivity of all the samples considered agreed closely with the literature values. A distinguishing feature of this technique is that it does not require a priori knowledge of the optical spot size which greatly increases measurement reliability and reproducibility.

  8. Penetration resistant barrier

    DOE Patents [OSTI]

    Hoover, William R.; Mead, Keith E.; Street, Henry K.

    1977-01-01

    The disclosure relates to a barrier for resisting penetration by such as hand tools and oxy-acetylene cutting torches. The barrier comprises a layer of firebrick, which is preferably epoxy impregnated sandwiched between inner and outer layers of steel. Between the firebrick and steel are layers of resilient rubber-like filler.

  9. Oxidation resistance of eight heat-resistant alloys at 870, 980...

    Office of Scientific and Technical Information (OSTI)

    Subject: 36 MATERIALS SCIENCE; HEAT RESISTING ALLOYS; CORROSION RESISTANCE; OXIDATION; ... COMPOUNDS; CHROMIUM-NICKEL STEELS; CORROSION RESISTANT ALLOYS; DATA; HEAT RESISTANT ...

  10. Solar Thermal Collector Manufacturing Activities

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

    9 Companies involved in solar thermal collector related activities by type, 2008 and 2009 ... 26 32 Source: U.S. Energy Information Administration, Form EIA-63A, "Annual Solar Thermal

  11. Solar Thermal Collector Manufacturing Activities

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

    8 Employment in the solar thermal collector industry, 2000 - 2009 2000 284 2001 256 2002 ... Source: U.S. Energy Information Administration, Form EIA-63A, "Annual Solar Thermal

  12. National Solar Thermal Test Facility

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

    SunShot Grand Challenge: Regional Test Centers National Solar Thermal Test Facility HomeTag:National Solar Thermal Test Facility Molten Nitrate Salt Initial Flow Testing is a ...

  13. Electro-thermal simulation of superconducting nanowire avalanche photodetectors

    SciTech Connect (OSTI)

    Marsili, F.; Najafi, F.; Herder, C.; Berggren, K. K.

    2011-01-01

    We developed an electrothermal model of NbN superconducting nanowire avalanche photodetectors (SNAPs) on sapphire substrates. SNAPs are single-photon detectors consisting of the parallel connection of N superconducting nanowires. We extrapolated the physical constants of the model from experimental data and we simulated the time evolution of the device resistance, temperature and current by solving two coupled electrical and thermal differential equations describing the nanowires. The predictions of the model were in good quantitative agreement with the experimental results.

  14. Thermally stable diamond brazing

    DOE Patents [OSTI]

    Radtke, Robert P.

    2009-02-10

    A cutting element and a method for forming a cutting element is described and shown. The cutting element includes a substrate, a TSP diamond layer, a metal interlayer between the substrate and the diamond layer, and a braze joint securing the diamond layer to the substrate. The thickness of the metal interlayer is determined according to a formula. The formula takes into account the thickness and modulus of elasticity of the metal interlayer and the thickness of the TSP diamond. This prevents the use of a too thin or too thick metal interlayer. A metal interlayer that is too thin is not capable of absorbing enough energy to prevent the TSP diamond from fracturing. A metal interlayer that is too thick may allow the TSP diamond to fracture by reason of bending stress. A coating may be provided between the TSP diamond layer and the metal interlayer. This coating serves as a thermal barrier and to control residual thermal stress.

  15. Thermal synthesis apparatus

    DOE Patents [OSTI]

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

    2009-08-18

    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.

  16. Underground Coal Thermal Treatment

    SciTech Connect (OSTI)

    Smith, P.; Deo, M.; Eddings, E.; Sarofim, A.; Gueishen, K.; Hradisky, M.; Kelly, K.; Mandalaparty, P.; Zhang, H.

    2012-01-11

    The long-term objective of this work is to develop a transformational energy production technology by insitu thermal treatment of a coal seam for the production of substitute natural gas (SNG) while leaving much of the coal's carbon in the ground. This process converts coal to a high-efficiency, low-GHG emitting gas fuel. It holds the potential of providing environmentally acceptable access to previously unusable coal resources. This topical report discusses the development of experimental capabilities, the collection of available data, and the development of simulation tools to obtain process thermo-chemical and geo-thermal parameters in preparation for the eventual demonstration in a coal seam. It also includes experimental and modeling studies of CO2 sequestration.

  17. National Solar Thermal Test Facility

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

    SunShot Grand Challenge: Regional Test Centers National Solar Thermal Test Facility Home/Tag:National Solar Thermal Test Facility Illuminated receiver on top of tower Permalink Gallery High-Temperature Falling Particle Receiver Reaches New Limits Concentrating Solar Power, Energy, National Solar Thermal Test Facility, News, Renewable Energy, Solar, SunShot High-Temperature Falling Particle Receiver Reaches New Limits At its National Solar Thermal Test Facility, Sandia National Laboratories

  18. Liquid metal thermal electric converter

    DOE Patents [OSTI]

    Abbin, Joseph P.; Andraka, Charles E.; Lukens, Laurance L.; Moreno, James B.

    1989-01-01

    A liquid metal thermal electric converter which converts heat energy to electrical energy. The design of the liquid metal thermal electric converter incorporates a unique configuration which directs the metal fluid pressure to the outside of the tube which results in the structural loads in the tube to be compressive. A liquid metal thermal electric converter refluxing boiler with series connection of tubes and a multiple cell liquid metal thermal electric converter are also provided.

  19. Thermally actuated thermionic switch

    DOE Patents [OSTI]

    Barrus, Donald M.; Shires, Charles D.

    1988-01-01

    A thermally actuated thermionic switch which responds to an increase of temperature by changing from a high impedance to a low impedance at a predictable temperature set point. The switch has a bistable operation mode switching only on temperature increases. The thermionic material may be a metal which is liquid at the desired operation temperature and held in matrix in a graphite block reservoir, and which changes state (ionizes, for example) so as to be electrically conductive at a desired temperature.

  20. THERMAL NEUTRONIC REACTOR

    DOE Patents [OSTI]

    Spinrad, B.I.

    1960-01-12

    A novel thermal reactor was designed in which a first reflector formed from a high atomic weight, nonmoderating material is disposed immediately adjacent to the reactor core. A second reflector composed of a moderating material is disposed outwardly of the first reflector. The advantage of this novel reflector arrangement is that the first reflector provides a high slow neutron flux in the second reflector, where irradiation experiments may be conducted with a small effect on reactor reactivity.

  1. Thermally actuated thermionic switch

    DOE Patents [OSTI]

    Barrus, D.M.; Shires, C.D.

    1982-09-30

    A thermally actuated thermionic switch which responds to an increase of temperature by changing from a high impedance to a low impedance at a predictable temperature set point. The switch has a bistable operation mode switching only on temperature increases. The thermionic material may be a metal which is liquid at the desired operation temperature and held in matrix in a graphite block reservoir, and which changes state (ionizes, for example) so as to be electrically conductive at a desired temperature.

  2. Thermal reactor safety

    SciTech Connect (OSTI)

    Not Available

    1980-06-01

    Information is presented concerning new trends in licensing; seismic considerations and system structural behavior; TMI-2 risk assessment and thermal hydraulics; statistical assessment of potential accidents and verification of computational methods; issues with respect to improved safety; human factors in nuclear power plant operation; diagnostics and activities in support of recovery; LOCA transient analysis; unresolved safety issues and other safety considerations; and fission product transport.

  3. Resistance after firing protected electric match. [Patent application

    DOE Patents [OSTI]

    Montoya, A.P.

    1980-03-20

    An electric match having electrical leads embedded in flame-producing compound is protected against an accidental resistance across the leads after firing by a length of heat-shrinkable tubing encircling the match body and having a skirt portion extending beyond the leads. The heat of the burning match and an adjacent thermal battery causes the tubing to fold over the end of the match body, covering the ends of the leads and protecting them from molten pieces of the battery.

  4. Resistive coating for current conductors in cryogenic applications

    DOE Patents [OSTI]

    Hirayama, Chikara; Wagner, George R.

    1982-05-18

    This invention relates to a resistive or semiconducting coating for use on current conductors in cryogenic applications. This includes copper-clad superconductor wire, copper wire used for stabilizing superconductor magnets, and for hyperconductors. The coating is a film of cuprous sulfide (Cu.sub.2 S) that has been found not to degrade the properties of the conductors. It is very adherent to the respective conductors and satisfies the mechanical, thermal and electrical requirements of coatings for the conductors.

  5. Power Electronic Thermal System Performance and Integration ...

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

    More Documents & Publications Motor Thermal Control Thermal Stress and Reliability for Advanced Power Electronics and Electric Machines Integrated Vehicle Thermal Management

  6. Solar Thermal Electric | Open Energy Information

    Open Energy Info (EERE)

    Thermal Electric Jump to: navigation, search TODO: Add description List of Solar Thermal Electric Incentives Retrieved from "http:en.openei.orgwindex.php?titleSolarThermalEl...

  7. Ocean Thermal Extractable Energy Visualization: Final Technical...

    Office of Environmental Management (EM)

    Ocean Thermal Extractable Energy Visualization: Final Technical Report Ocean Thermal Extractable Energy Visualization: Final Technical Report Report about the Ocean Thermal ...

  8. Methods of forming thermal management systems and thermal management methods

    DOE Patents [OSTI]

    Gering, Kevin L.; Haefner, Daryl R.

    2012-06-05

    A thermal management system for a vehicle includes a heat exchanger having a thermal energy storage material provided therein, a first coolant loop thermally coupled to an electrochemical storage device located within the first coolant loop and to the heat exchanger, and a second coolant loop thermally coupled to the heat exchanger. The first and second coolant loops are configured to carry distinct thermal energy transfer media. The thermal management system also includes an interface configured to facilitate transfer of heat generated by an internal combustion engine to the heat exchanger via the second coolant loop in order to selectively deliver the heat to the electrochemical storage device. Thermal management methods are also provided.

  9. Thermal conductivity of III-V semiconductor superlattices

    SciTech Connect (OSTI)

    Mei, S. Knezevic, I.

    2015-11-07

    This paper presents a semiclassical model for the anisotropic thermal transport in III-V semiconductor superlattices (SLs). An effective interface rms roughness is the only adjustable parameter. Thermal transport inside a layer is described by the Boltzmann transport equation in the relaxation time approximation and is affected by the relevant scattering mechanisms (three-phonon, mass-difference, and dopant and electron scattering of phonons), as well as by diffuse scattering from the interfaces captured via an effective interface scattering rate. The in-plane thermal conductivity is obtained from the layer conductivities connected in parallel. The cross-plane thermal conductivity is calculated from the layer thermal conductivities in series with one another and with thermal boundary resistances (TBRs) associated with each interface; the TBRs dominate cross-plane transport. The TBR of each interface is calculated from the transmission coefficient obtained by interpolating between the acoustic mismatch model (AMM) and the diffuse mismatch model (DMM), where the weight of the AMM transmission coefficient is the same wavelength-dependent specularity parameter related to the effective interface rms roughness that is commonly used to describe diffuse interface scattering. The model is applied to multiple III-arsenide superlattices, and the results are in very good agreement with experimental findings. The method is both simple and accurate, easy to implement, and applicable to complicated SL systems, such as the active regions of quantum cascade lasers. It is also valid for other SL material systems with high-quality interfaces and predominantly incoherent phonon transport.

  10. Corrosion-resistant metal surfaces

    DOE Patents [OSTI]

    Sugama, Toshifumi

    2009-03-24

    The present invention relates to metal surfaces having thereon an ultrathin (e.g., less than ten nanometer thickness) corrosion-resistant film, thereby rendering the metal surfaces corrosion-resistant. The corrosion-resistant film includes an at least partially crosslinked amido-functionalized silanol component in combination with rare-earth metal oxide nanoparticles. The invention also relates to methods for producing such corrosion-resistant films.

  11. Electrical resistivity probes

    DOE Patents [OSTI]

    Lee, Ki Ha; Becker, Alex; Faybishenko, Boris A.; Solbau, Ray D.

    2003-10-21

    A miniaturized electrical resistivity (ER) probe based on a known current-voltage (I-V) electrode structure, the Wenner array, is designed for local (point) measurement. A pair of voltage measuring electrodes are positioned between a pair of current carrying electrodes. The electrodes are typically about 1 cm long, separated by 1 cm, so the probe is only about 1 inch long. The electrodes are mounted to a rigid tube with electrical wires in the tube and a sand bag may be placed around the electrodes to protect the electrodes. The probes can be positioned in a borehole or on the surface. The electrodes make contact with the surrounding medium. In a dual mode system, individual probes of a plurality of spaced probes can be used to measure local resistance, i.e. point measurements, but the system can select different probes to make interval measurements between probes and between boreholes.

  12. Corrosive resistant heat exchanger

    DOE Patents [OSTI]

    Richlen, Scott L.

    1989-01-01

    A corrosive and errosive resistant heat exchanger which recovers heat from a contaminated heat stream. The heat exchanger utilizes a boundary layer of innocuous gas, which is continuously replenished, to protect the heat exchanger surface from the hot contaminated gas. The innocuous gas is conveyed through ducts or perforations in the heat exchanger wall. Heat from the heat stream is transferred by radiation to the heat exchanger wall. Heat is removed from the outer heat exchanger wall by a heat recovery medium.

  13. Electric Resistance Heating | Department of Energy

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

    Electric Resistance Heating Electric Resistance Heating Baseboard heaters are one type of electric resistance heaters. | Photo courtesy of iStockphotodrewhadley...

  14. Thermal control structure and garment

    DOE Patents [OSTI]

    Klett, James W.; Cameron, Christopher Stan

    2012-03-13

    A flexible thermally conductive structure. The structure generally includes a plurality of thermally conductive yarns, at least some of which are at least partially disposed adjacent to an elastomeric material. Typically, at least a portion of the plurality of thermally conductive yarns is configured as a sheet. The yarns may be constructed from graphite, metal, or similar materials. The elastomeric material may be formed from urethane or silicone foam that is at least partially collapsed, or from a similar material. A thermal management garment is provided, the garment incorporating a flexible thermally conductive structure.

  15. Thermal Performance of Uninsulated and Partially Filled Wall Cavities: Preprint

    SciTech Connect (OSTI)

    Ridouane, E. H.; Bianchi, M.

    2011-08-01

    Low-rise, wood-framed homes are the most common type of residential structures in the United States. Wood wall construction supports roofs efficiently and provides a stable frame for attaching interior and exterior wall coverings. Wall cavities are prevalent and increase thermal resistance, particularly when they are filled with insulating material. This paper describes detailed computational fluid dynamics modeling to evaluate the thermal performance of uninsulated or partially filled wall cavities and accounts for conduction through framing, convection, and radiation. Parameters are ambient outdoor temperature, cavity surface emissivity, cavity aspect ratio, and insulation height. Understanding the thermal performance of uninsulated or partially insulated wall cavities is essential for conserving energy in residential buildings. The results can serve as input for building energy simulation tools such as DOE2 and EnergyPlus for modeling the temperature dependent energy performance of new and older homes with uninsulated or partially insulated walls.

  16. Degenerate resistive switching and ultrahigh density storage in resistive memory

    SciTech Connect (OSTI)

    Lohn, Andrew J. Mickel, Patrick R. James, Conrad D.; Marinella, Matthew J.

    2014-09-08

    We show that in tantalum oxide resistive memories, activation power provides a multi-level variable for information storage that can be set and read separately from the resistance. These two state variables (resistance and activation power) can be precisely controlled in two steps: (1) the possible activation power states are selected by partially reducing resistance, then (2) a subsequent partial increase in resistance specifies the resistance state and the final activation power state. We show that these states can be precisely written and read electrically, making this approach potentially amenable for ultra-high density memories. We provide a theoretical explanation for information storage and retrieval from activation power and experimentally demonstrate information storage in a third dimension related to the change in activation power with resistance.

  17. Factors affecting the microstructural stability and durability of thermal barrier coatings fabricated by air plasma spraying

    SciTech Connect (OSTI)

    Helminiak, M. A.; Yanar, N. M.; Pettit, F. S.; Taylor, T. A.; Meier, G. H.

    2012-10-01

    The high-temperature behavior of high-purity, low-density (HP-LD) air plasma sprayed (APS) thermal barrier coatings (TBCs) with NiCoCrAlY bond coats deposited by argon-shrouded plasma spraying is described. The high purity yttria-stabilized zirconia resulted in top coats which are highly resistant to sintering and transformation from the metastable tetragonal phase to the equilibrium mixture of monoclinic and cubic phases. The thermal conductivity of the as-processed TBC is low but increases during high temperature exposure even before densification occurs. The porous topcoat microstructure also resulted in good spallation resistance during thermal cycling. The actual failure mechanisms of the APS coatings were found to depend on topcoat thickness, topcoat density, and the thermal cycle frequency. The failure mechanisms are described and the durability of the HP-LD coatings is compared with that of state-of-the-art electron beam physical vapor deposition TBCs.

  18. Thermal management systems and methods

    DOE Patents [OSTI]

    Gering, Kevin L.; Haefner, Daryl R.

    2006-12-12

    A thermal management system for a vehicle includes a heat exchanger having a thermal energy storage material provided therein, a first coolant loop thermally coupled to an electrochemical storage device located within the first coolant loop and to the heat exchanger, and a second coolant loop thermally coupled to the heat exchanger. The first and second coolant loops are configured to carry distinct thermal energy transfer media. The thermal management system also includes an interface configured to facilitate transfer of heat generated by an internal combustion engine to the heat exchanger via the second coolant loop in order to selectively deliver the heat to the electrochemical storage device. Thermal management methods are also provided.

  19. Update on R-Value Measurements @ NCERC (Conference) | SciTech...

    Office of Scientific and Technical Information (OSTI)

    Resource Relation: Conference: NCNS F2012 Quarterly NPPR Review ; 2012-07-11 - 2012-07-12 ; Albuquerque, New Mexico, United States Research Org: Los Alamos National Laboratory ...

  20. Update on R-Value Measurements @ NCERC (Conference) | SciTech...

    Office of Scientific and Technical Information (OSTI)

    Visit OSTI to utilize additional information resources in energy science and technology. A ... - 2012-07-12 ; Albuquerque, New Mexico, United States Research Org: Los Alamos ...

  1. Thermal Design and Characterization of Heterogeneously Integrated InGaP/GaAs HBTs

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Choi, Sukwon; Peake, Gregory M.; Keeler, Gordon A.; Geib, Kent M.; Briggs, Ronald D.; Beechem, Thomas E.; Shaffer, Ryan A.; Clevenger, Jascinda; Patrizi, Gary A.; Klem, John F.; et al

    2016-04-21

    Flip-chip heterogeneously integrated n-p-n InGaP/GaAs heterojunction bipolar transistors (HBTs) with integrated thermal management on wide-bandgap AlN substrates followed by GaAs substrate removal are demonstrated. Without thermal management, substrate removal after integration significantly aggravates self-heating effects, causing poor I–V characteristics due to excessive device self-heating. An electrothermal codesign scheme is demonstrated that involves simulation (design), thermal characterization, fabrication, and evaluation. Thermoreflectance thermal imaging, electrical-temperature sensitive parameter-based thermometry, and infrared thermography were utilized to assess the junction temperature rise in HBTs under diverse configurations. In order to reduce the thermal resistance of integrated devices, passive cooling schemes assisted by structural modification, i.e.,more » positioning indium bump heat sinks between the devices and the carrier, were employed. By implementing thermal heat sinks in close proximity to the active region of flip-chip integrated HBTs, the junction-to-baseplate thermal resistance was reduced over a factor of two, as revealed by junction temperature measurements and improvement of electrical performance. In conclusion, the suggested heterogeneous integration method accounts for not only electrical but also thermal requirements providing insight into realization of advanced and robust III–V/Si heterogeneously integrated electronics.« less

  2. Thermally switchable dielectrics

    DOE Patents [OSTI]

    Dirk, Shawn M.; Johnson, Ross S.

    2013-04-30

    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.

  3. Response microcantilever thermal detector

    DOE Patents [OSTI]

    Cunningham, Joseph P.; Rajic, Slobodan; Datskos, Panagiotis G.; Evans III, Boyd M.

    2004-10-19

    A "folded leg" thermal detector microcantilever constructed of a substrate with at least one leg interposed between a fixed end and a deflective end, each leg having at least three essentially parallel leg segments interconnected on alternate opposing ends and aligned in a serpentine pattern with only the first leg segment attached to the fixed end and only the last leg segment attached to the deflective end. Alternate leg segment are coated on the pentalever with coating applied to the top of the first, third, and fifth leg segments of each leg and to the bottom of the second and fourth leg segments of each leg.

  4. Thermally cleavable surfactants

    DOE Patents [OSTI]

    McElhanon, James R.; Simmons, Blake A.; Zifer, Thomas; Jamison, Gregory M.; Loy, Douglas A.; Rahimian, Kamyar; Long, Timothy M.; Wheeler, David R.; Staiger, Chad L.

    2009-09-29

    Two new surfactant molecules are reported which contain thermally labile Diels-Alder adducts connecting the polar and non-polar sections of each molecule. The two surfactants possess identical non-polar dodecyl tail segments but exhibit different polar headgroups. The surfactants become soluble in water when anionic salts are formed through the deprotonation of the surfactant headgroups by the addition of potassium hydroxide. When either surfactant is exposed to temperature above about 60.degree. C., the retro Diels-Alder reaction occurs, yielding hydrophilic and hydrophobic fragments or the aqueous solutions of the surfactants subsequently exhibit loss of all surface-active behavior.

  5. Thermally cleavable surfactants

    DOE Patents [OSTI]

    McElhanon, James R.; Simmons, Blake A.; Zifer, Thomas; Jamison, Gregory M.; Loy, Douglas A.; Rahimian, Kamyar; Long, Timothy M.; Wheeler, David R.; Staiger, Chad L.

    2009-11-24

    Two new surfactant molecules are reported which contain thermally labile Diels-Alder adducts connecting the polar and non-polar sections of each molecule. The two surfactants possess identical non-polar dodecyl tail segments but exhibit different polar headgroups. The surfactants become soluble in water when anionic salts are formed through the deprotonation of the surfactant headgroups by the addition of potassium hydroxide. When either surfactant is exposed to temperature above about 60.degree. C., the retro Diels-Alder reaction occurs, yielding hydrophilic and hydrophobic fragments or the aqueous solutions of the surfactants subsequently exhibit loss of all surface-active behavior.

  6. Thermal network reduction

    SciTech Connect (OSTI)

    Balcomb, J.D.

    1983-01-01

    A method is presented for reducing the number of elements required in a thermal network representation of a building. The method is based on matching the actual building response at two frequencies, the diurnal response and 3-day response. The procedure provides a straightforward methodology for combining all the various materials inside a discrete building zone into a few nodes while retaining a high degree of accuracy in the dynamic response. An example is given showing a comparison between a large network and the reduced network.

  7. Thermal network reduction

    SciTech Connect (OSTI)

    Balcomb, J.D.

    1983-06-01

    A method is presented for reducing the number of elements required in a thermal network representation of a building. The method is based on matching the actual building response at two frequencies, the diurnal response and 3-day response. The procedure provides a straightforward methodology for combining all the various materials inside a discrete building zone into a few nodes while retaining a high degree of accuracy in the dynamic response. An example is given showing a comparison between a large network and the reduced network.

  8. Thermal transient anemometer

    DOE Patents [OSTI]

    Bailey, J.L.; Vresk, J.

    1989-07-18

    A thermal transient anemometer is disclosed having a thermocouple probe which is utilized to measure the change in temperature over a period of time to provide a measure of fluid flow velocity. The thermocouple probe is located in the fluid flow path and pulsed to heat or cool the probe. The cooling of the heated probe or the heating of the cooled probe from the fluid flow over a period of time is measured to determine the fluid flow velocity. The probe is desired to be locally heated near the tip to increase the efficiency of devices incorporating the probe. 12 figs.

  9. Thermally cleavable surfactants

    DOE Patents [OSTI]

    McElhanon, James R.; Simmons, Blake A.; Zifer, Thomas; Jamison, Gregory M.; Loy, Douglas A.; Rahimian, Kamyar; Long, Timothy M.; Wheeler, David R.; Staiger, Chad L.

    2006-04-04

    Two new surfactant molecules are reported which contain thermally labile Diels-Alder adducts connecting the polar and non-polar sections of each molecule. The two surfactants possess identical non-polar dodecyl tail segments but exhibit different polar headgroups. The surfactants become soluble in water when anionic salts are formed through the deprotonation of the surfactant headgroups by the addition of potassium hydroxide. When either surfactant is exposed to temperature above about 60.degree. C., the retro Diels-Alder reaction occurs, yielding hydrophilic and hydrophobic fragments and the aqueous solutions of the surfactants subsequently exhibit loss of all surface-active behavior.

  10. Thermal transient anemometer

    DOE Patents [OSTI]

    Bailey, James L.; Vresk, Josip

    1989-01-01

    A thermal transient anemometer having a thermocouple probe which is utilized to measure the change in temperature over a period of time to provide a measure of fluid flow velocity. The thermocouple probe is located in the fluid flow path and pulsed to heat or cool the probe. The cooling of the heated probe or the heating of the cooled probe from the fluid flow over a period of time is measured to determine the fluid flow velocity. The probe is desired to be locally heated near the tip to increase the efficiency of devices incorporating the probe.

  11. MESO-SCALE MODELING OF THE INFLUENCE OF INTERGRANULAR GAS BUBBLES ON EFFECTIVE THERMAL CONDUCTIVITY

    SciTech Connect (OSTI)

    Paul C. Millett; Michael Tonks

    2011-06-01

    Using a mesoscale modeling approach, we have investigated how intergranular fission gas bubbles, as observed in high-burnup nuclear fuel, modify the effective thermal conductivity in a polycrystalline material. The calculations reveal that intergranular porosity has a significantly higher resistance to heat transfer compared to randomly-distributed porosity. A model is developed to describe this conductivity reduction that considers an effective grain boundary Kapitza resistance as a function of the fractional coverage of grain boundaries by bubbles.

  12. Thermal properties and use of cellulosic insulation produced from recycled paper

    SciTech Connect (OSTI)

    Yarbrough, D.W.; Wilkes, K.E.

    1996-10-01

    Information regarding the use of building insulation made from recycled paper is summarized. Results of previous experimental studies to determine thermal conductivities, settled density, and flammability are outlined, and calculation methods for thermal resistivity are presented in detail. Other performance factors affecting installed insulation are discussed. Industry data and information on the production, use, and economics of cellulosic insulation for residential and commercial buildings are provided. 34 refs., 4 figs., 1 tab.

  13. Prediction of Thermal Conductivity for Irradiated SiC/SiC Composites by Informing Continuum Models with Molecular Dynamics Data

    SciTech Connect (OSTI)

    Nguyen, Ba Nghiep; Gao, Fei; Henager, Charles H.; Kurtz, Richard J.

    2014-05-01

    This article proposes a new method to estimate the thermal conductivity of SiC/SiC composites subjected to neutron irradiation. The modeling method bridges different scales from the atomic scale to the scale of a 2D SiC/SiC composite. First, it studies the irradiation-induced point defects in perfect crystalline SiC using molecular dynamics (MD) simulations to compute the defect thermal resistance as a function of vacancy concentration and irradiation dose. The concept of defect thermal resistance is explored explicitly in the MD data using vacancy concentrations and thermal conductivity decrements due to phonon scattering. Point defect-induced swelling for chemical vapor deposited (CVD) SiC as a function of irradiation dose is approximated by scaling the corresponding MD results for perfect crystal ?-SiC to experimental data for CVD-SiC at various temperatures. The computed thermal defect resistance, thermal conductivity as a function of grain size, and definition of defect thermal resistance are used to compute the thermal conductivities of CVD-SiC, isothermal chemical vapor infiltrated (ICVI) SiC and nearly-stoichiometric SiC fibers. The computed fiber and ICVI-SiC matrix thermal conductivities are then used as input for an Eshelby-Mori-Tanaka approach to compute the thermal conductivities of 2D SiC/SiC composites subjected to neutron irradiation within the same irradiation doses. Predicted thermal conductivities for an irradiated Tyranno-SA/ICVI-SiC composite are found to be comparable to available experimental data for a similar composite ICVI-processed with these fibers.

  14. Thermomechanical measurements on thermal microactuators. (Technical...

    Office of Scientific and Technical Information (OSTI)

    Thermal and mechanical measurements for the bent-beam polycrystalline silicon thermal ... SANDIA NATIONAL LABORATORIES; SILICON; VALIDATION Microactuators.; Ceramic ...

  15. Integrated Vehicle Thermal Management Systems (VTMS) Analysis...

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

    More Documents & Publications Integrated Vehicle Thermal Management Power Electronic Thermal System Performance and Integration Characterization and Development of Advanced...

  16. Solar thermal power system

    SciTech Connect (OSTI)

    Bennett, Charles L.

    2010-06-15

    A solar thermal power generator includes an inclined elongated boiler tube positioned in the focus of a solar concentrator for generating steam from water. The boiler tube is connected at one end to receive water from a pressure vessel as well as connected at an opposite end to return steam back to the vessel in a fluidic circuit arrangement that stores energy in the form of heated water in the pressure vessel. An expander, condenser, and reservoir are also connected in series to respectively produce work using the steam passed either directly (above a water line in the vessel) or indirectly (below a water line in the vessel) through the pressure vessel, condense the expanded steam, and collect the condensed water. The reservoir also supplies the collected water back to the pressure vessel at the end of a diurnal cycle when the vessel is sufficiently depressurized, so that the system is reset to repeat the cycle the following day. The circuital arrangement of the boiler tube and the pressure vessel operates to dampen flow instabilities in the boiler tube, damp out the effects of solar transients, and provide thermal energy storage which enables time shifting of power generation to better align with the higher demand for energy during peak energy usage periods.

  17. Corrosion-resistant uranium

    DOE Patents [OSTI]

    Hovis, V.M. Jr.; Pullen, W.C.; Kollie, T.G.; Bell, R.T.

    1981-10-21

    The present invention is directed to the protecting of uranium and uranium alloy articles from corrosion by providing the surfaces of the articles with a layer of an ion-plated metal selected from aluminum and zinc to a thickness of at least 60 microinches and then converting at least the outer surface of the ion-plated layer of aluminum or zinc to aluminum chromate or zinc chromate. This conversion of the aluminum or zinc to the chromate form considerably enhances the corrosion resistance of the ion plating so as to effectively protect the coated article from corrosion.

  18. Corrosion-resistant uranium

    DOE Patents [OSTI]

    Hovis, Jr., Victor M.; Pullen, William C.; Kollie, Thomas G.; Bell, Richard T.

    1983-01-01

    The present invention is directed to the protecting of uranium and uranium alloy articles from corrosion by providing the surfaces of the articles with a layer of an ion-plated metal selected from aluminum and zinc to a thickness of at least 60 microinches and then converting at least the outer surface of the ion-plated layer of aluminum or zinc to aluminum chromate or zinc chromate. This conversion of the aluminum or zinc to the chromate form considerably enhances the corrosion resistance of the ion plating so as to effectively protect the coated article from corrosion.

  19. Abrasion resistant composition

    DOE Patents [OSTI]

    Fischer, Keith D; Barnes, Christopher A; Henderson, Stephen L

    2014-05-13

    A surface covering composition of abrasion resistant character adapted for disposition in overlying bonded relation to a metal substrate. The surface covering composition includes metal carbide particles within a metal matrix at a packing factor of not less than about 0.6. Not less than about 40 percent by weight of the metal carbide particles are characterized by an effective diameter in the range of +14-32 mesh prior to introduction to the metal matrix. Not less than about 3 percent by weight of the metal carbide particles are characterized by an effective diameter of +60 mesh prior to introduction to the metal matrix.

  20. Electric Vehicle Battery Thermal Issues and Thermal Management Techniques (Presentation)

    SciTech Connect (OSTI)

    Rugh, J. P.; Pesaran, A.; Smith, K.

    2013-07-01

    This presentation examines the issues concerning thermal management in electric drive vehicles and management techniques for improving the life of a Li-ion battery in an EDV.

  1. Resistive hydrogen sensing element

    DOE Patents [OSTI]

    Lauf, Robert J.

    2000-01-01

    Systems and methods are described for providing a hydrogen sensing element with a more robust exposed metallization by application of a discontinuous or porous overlay to hold the metallization firmly on the substrate. An apparatus includes: a substantially inert, electrically-insulating substrate; a first Pd containing metallization deposited upon the substrate and completely covered by a substantially hydrogen-impermeable layer so as to form a reference resistor on the substrate; a second Pd containing metallization deposited upon the substrate and at least a partially accessible to a gas to be tested, so as to form a hydrogen-sensing resistor; a protective structure disposed upon at least a portion of the second Pd containing metallization and at least a portion of the substrate to improve the attachment of the second Pd containing metallization to the substrate while allowing the gas to contact said the second Pd containing metallization; and a resistance bridge circuit coupled to both the first and second Pd containing metallizations. The circuit determines the difference in electrical resistance between the first and second Pd containing metallizations. The hydrogen concentration in the gas may be determined. The systems and methods provide advantages because adhesion is improved without adversely effecting measurement speed or sensitivity.

  2. Oxidation Resistant Graphite Studies

    SciTech Connect (OSTI)

    W. Windes; R. Smith

    2014-07-01

    The Very High Temperature Reactor (VHTR) Graphite Research and Development Program is investigating doped nuclear graphite grades exhibiting oxidation resistance. During a oxygen ingress accident the oxidation rates of the high temperature graphite core region would be extremely high resulting in significant structural damage to the core. Reducing the oxidation rate of the graphite core material would reduce the structural effects and keep the core integrity intact during any air-ingress accident. Oxidation testing of graphite doped with oxidation resistant material is being conducted to determine the extent of oxidation rate reduction. Nuclear grade graphite doped with varying levels of Boron-Carbide (B4C) was oxidized in air at nominal 740°C at 10/90% (air/He) and 100% air. The oxidation rates of the boronated and unboronated graphite grade were compared. With increasing boron-carbide content (up to 6 vol%) the oxidation rate was observed to have a 20 fold reduction from unboronated graphite. Visual inspection and uniformity of oxidation across the surface of the specimens were conducted. Future work to determine the remaining mechanical strength as well as graphite grades with SiC doped material are discussed.

  3. Skew resisting hydrodynamic seal

    DOE Patents [OSTI]

    Conroy, William T.; Dietle, Lannie L.; Gobeli, Jeffrey D.; Kalsi, Manmohan S.

    2001-01-01

    A novel hydrodynamically lubricated compression type rotary seal that is suitable for lubricant retention and environmental exclusion. Particularly, the seal geometry ensures constraint of a hydrodynamic seal in a manner preventing skew-induced wear and provides adequate room within the seal gland to accommodate thermal expansion. The seal accommodates large as-manufactured variations in the coefficient of thermal expansion of the sealing material, provides a relatively stiff integral spring effect to minimize pressure-induced shuttling of the seal within the gland, and also maintains interfacial contact pressure within the dynamic sealing interface in an optimum range for efficient hydrodynamic lubrication and environment exclusion. The seal geometry also provides for complete support about the circumference of the seal to receive environmental pressure, as compared the interrupted character of seal support set forth in U.S. Pat. Nos. 5,873,576 and 6,036,192 and provides a hydrodynamic seal which is suitable for use with non-Newtonian lubricants.

  4. Calibrating thermal behavior of electronics

    DOE Patents [OSTI]

    Chainer, Timothy J.; Parida, Pritish R.; Schultz, Mark D.

    2016-05-31

    A method includes determining a relationship between indirect thermal data for a processor and a measured temperature associated with the processor, during a calibration process, obtaining the indirect thermal data for the processor during actual operation of the processor, and determining an actual significant temperature associated with the processor during the actual operation using the indirect thermal data for the processor during actual operation of the processor and the relationship.

  5. 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)

    2002-01-01

    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.

  6. Overview of solar thermal technologies

    SciTech Connect (OSTI)

    None, None

    2009-01-18

    The solar-thermal overview section of the Renewable Energy Technology Characterizations describes the technical and economic status of this emerging renewable energy option for electricity supply.

  7. SUPERFAST THERMALIZATION OF PLASMA

    DOE Patents [OSTI]

    Chang, C.C.

    1962-06-12

    A method is given for the superfast thermalization of plasma by shock conversion of the kinetic energy stored in rotating plasma rings or plasmoids colliding at near supersonic speeds in a containment field to heat energy in the resultant confined plasma mass. The method includes means for generating rotating plasmoids at the opposite ends of a Pyrotron or Astron containment field. The plasmoids are magnetically accelerated towards each other into the opposite ends of time containment field. During acceleration of the plasmoids toward the center of the containment field, the intensity of the field is sequentially increased to adiabatically compress the plasmoids and increase the plasma energy. The plasmoids hence collide with a violent shock at the eenter of the containment field, causing the substantial kinetic energy stored in the plasmoids to be converted to heat in the resultant plasma mass. (AEC)

  8. Thermally stabilized heliostat

    DOE Patents [OSTI]

    Anderson, Alfred J.

    1983-01-01

    An improvement in a heliostat having a main support structure and pivoting and tilting motors and gears and a mirror module for reflecting solar energy onto a collector, the improvement being characterized by an internal support structure within each mirror module and front and back sheets attached to the internal support structure, the front and back sheets having the same coefficient of thermal expansion such that no curvature is induced by temperature change, and a layer of adhesive adhering the mirror to the front sheet. The adhesive is water repellent and has adequate set strength to support the mirror but has sufficient shear tolerance to permit the differential expansion of the mirror and the front sheet without inducing stresses or currature effect. The adhesive also serves to dampen fluttering of the mirror and to protect the mirror backside against the adverse effects of weather. Also disclosed are specific details of the preferred embodiment.

  9. THERMALLY OPERATED VAPOR VALVE

    DOE Patents [OSTI]

    Dorward, J.G. Jr.

    1959-02-10

    A valve is presented for use in a calutron to supply and control the vapor to be ionized. The invention provides a means readily operable from the exterior of the vacuum tank of the apparatuss without mechanical transmission of forces for the quick and accurate control of the ionizing arc by a corresponding control of gas flow theretos thereby producing an effective way of carefully regulating the operation of the calutron. The invention consists essentially of a tube member extending into the charge bottle of a calutron devices having a poppet type valve closing the lower end of the tube. An electrical heating means is provided in the valve stem to thermally vary the length of the stem to regulate the valve opening to control the flow of material from the charge bottle.

  10. Thermal protection apparatus

    DOE Patents [OSTI]

    Bennett, Gloria A.; Moore, Troy K.

    1988-01-01

    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.