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Measurements of thermal distortion of the submarine intermediate reactor "Mark A" moderator tube

Description: Report presenting a moderator tube of the Submarine Intermediate Reactor (SIR) ("Mark A") subjected to temperature gradients considered to be representative of those occurring in the reactor during operation. The distortion of the tube was measured under two conditions: with the ends of the tube retained in the same manner at the reactor and with the ends of the tube simply supported.
Date: December 1952
Creator: Kemp, R. H. & Morgan, W. C.
Partner: UNT Libraries Government Documents Department

Generation of Compositionally Graded Ga{sub 1-x}In{sub x}Sb Seed by Solute Diffusion

Description: Compositionally graded single crystalline <100> seed of Ga{sub 1-x}In{sub x}Sb has been grown in a single experiment using a solute diffusion method. The present technique is simple and less time consuming compared to the conventional boot-strapping approach previously used for generating ternary seeds. Starting from an InSb <100> single crystalline seed, a seed of Ga{sub 0.6}In{sub 0.4}Sb has been grown. The effect of temperature gradient on the crystalline quality of seeds grown using this method has been discussed.
Date: August 29, 2002
Creator: Dutta, P.S.; Rajagopalan, G.; Gutmann, R.J. & Nichols, G.
Partner: UNT Libraries Government Documents Department

Sound Propagation Into the Shadow Zone in a Temperature-Stratified Atmosphere Above a Plane Boundary

Description: Note presenting an investigation of the sound field about a point source over a plane boundary in the presence of a vertical temperature gradient, which represents one phase of a general program of research in atmospheric acoustics. In this report, geometrical ray acoustics is employed to derive the ray paths and intensity distribution about a source located in a uniformly stratified medium. Results indicate that the existence of a temperature gradient, which leads only to a simple refraction of sound rays, can be in conjunction with the ground boundary result in the formation of a "shadow zone".
Date: October 1955
Creator: Pridmore-Brown, David C. & Ingard, Uno
Partner: UNT Libraries Government Documents Department

Determination of the Evaporation Coefficient of D2O

Description: The evaporation rate of D{sub 2}O has been determined by Raman thermometry of a droplet train (12-15 {micro}m diameter) injected into vacuum ({approx}10{sup -5} torr). The cooling rate measured as a function of time in vacuum was fit to a model that accounts for temperature gradients between the surface and the core of the droplets, yielding an evaporation coefficient ({gamma}{sub e}) of 0.57 {+-} 0.06. This is nearly identical to that found for H{sub 2}O (0.62 {+-} 0.09) using the same experimental method and model, and indicates the existence of a kinetic barrier to evaporation. The application of a recently developed transition state theory (TST) model suggests that the kinetic barrier is due to librational and hindered translational motions at the liquid surface, and that the lack of an isotope effect is due to competing energetic and entropic factors. The implications of these results for cloud and aerosol particles in the atmosphere are discussed.
Date: March 26, 2008
Creator: Drisdell, Walter S.; Cappa, Christopher D.; Smith, Jared D.; Saykally, Richard J. & Cohen, Ronald C.
Partner: UNT Libraries Government Documents Department

Thermal, Electrical and Mechanical Response to a Quench in Nb3Sn Superconducting Coils

Description: During a quench, significant temperatures can arise as a magnet's stored energy is dissipated in the normal zone. Temperature gradients during this process give rise to localized strains within the coil. Reactive forces in the magnet structure balance the electromagnetic and thermal forces and maintain on equilibrium. In this paper we present a complete 3D finite element analysis of a racetrack coil. Specifically, the analysis focuses on thermal, electrical and mechanical conditions in a 10T Nb{sub 3}Sn coil built and tested as part of LBNL's Subscale Magnet Program. The study attempts to simulate time history of the temperature and voltage rise during quench propagation. The transient thermal stress after the quench is then evaluated and discussed.
Date: October 1, 2003
Creator: Ferracin, P.; Caspi, S.; Chiesa, L.; Gourlay, S.A.; Hafalia, R.r.; Imbasciati, L. et al.
Partner: UNT Libraries Government Documents Department

Thermal, Electrical and Mechanical Response to a Quench in Nb3SnSuperconducting Coils

Description: During a quench, significant temperatures can arise as a magnet's stored energy is dissipated in the normal zone. Temperature gradients during this process give rise to localized strains within the coil. Reactive forces in the magnet structure balance the electromagnetic and thermal forces and maintain on equilibrium. In this paper we present a complete 3D finite element analysis of a racetrack coil. Specifically, the analysis focuses on thermal, electrical and mechanical conditions in a 10 T Nb{sub 3}Sn coil built and tested as part of LBNL's Subscale Magnet Program. The study attempts to simulate time history of the temperature and voltage rise during quench propagation. The transient thermal stress after the quench is then evaluated and discussed.
Date: November 10, 2003
Creator: Ferracin, F.; Caspi, S.; Chiesa, L.; Gourlay, S.A.; Hafalia,R.R.; Imbasciati, L. et al.
Partner: UNT Libraries Government Documents Department

AERIAL MEASUREMENTS OF CONVECTION CELL ELEMENTS IN HEATED LAKES

Description: Power plant-heated lakes are characterized by a temperature gradient in the thermal plume originating at the discharge of the power plant and terminating at the water intake. The maximum water temperature discharged by the power plant into the lake depends on the power generated at the facility and environmental regulations on the temperature of the lake. Besides the observed thermal plume, cloud-like thermal cells (convection cell elements) are also observed on the water surface. The size, shape and temperature of the convection cell elements depends on several parameters such as the lake water temperature, wind speed, surfactants and the depth of the thermocline. The Savannah River National Laboratory (SRNL) and Clemson University are collaborating to determine the applicability of laboratory empirical correlations between surface heat flux and thermal convection intensity. Laboratory experiments at Clemson University have demonstrated a simple relationship between the surface heat flux and the standard deviation of temperature fluctuations. Similar results were observed in the aerial thermal imagery SRNL collected at different locations along the thermal plume and at different elevations. SRNL will present evidence that the results at Clemson University are applicable to cooling lakes.
Date: December 19, 2007
Creator: Villa-Aleman, E; Saleem Salaymeh, S; Timothy Brown, T; Alfred Garrett, A; Malcolm Pendergast, M & Linda Nichols, L
Partner: UNT Libraries Government Documents Department

DIRECT MEASUREMENT OF HEAT FLUX FROM COOLING LAKE THERMAL IMAGERY

Description: Laboratory experiments show a linear relationship between the total heat flux from a water surface to air and the standard deviation of the surface temperature field, {sigma}, derived from thermal images of the water surface over a range of heat fluxes from 400 to 1800 Wm{sup -2}. Thermal imagery and surface data were collected at two power plant cooling lakes to determine if the laboratory relationship between heat flux and {sigma} exists in large heated bodies of water. The heat fluxes computed from the cooling lake data range from 200 to 1400 Wm{sup -2}. The linear relationship between {sigma} and Q is evident in the cooling lake data, but it is necessary to apply band pass filtering to the thermal imagery to remove camera artifacts and non-convective thermal gradients. The correlation between {sigma} and Q is improved if a correction to the measured {sigma} is made that accounts for wind speed effects on the thermal convection. Based on more than a thousand cooling lake images, the correlation coefficients between {sigma} and Q ranged from about 0.8 to 0.9.
Date: December 19, 2007
Creator: Garrett, A; Eliel Villa-Aleman, E; Robert Kurzeja, R; Malcolm Pendergast, M; Timothy Brown, T & Saleem Salaymeh, S
Partner: UNT Libraries Government Documents Department

Geology and Thermal Regime of Bert Winn #1 geothermal Test, Franklin County, Idaho

Description: The conclusions of this report are: (1) Bert Winn No.1 did not encounter high-temperature zones of permeability, except possibly at 5,575 to 5,700 feet, where chloride conductivity indicates saline fluid entry, and where stabilized temperature may be 210-215 F. (2) Structurally, Bert Winn No.1 appears to have penetrated into the horst footwall block, penetrating progressively away from the horst-bounding faults believed to leak hot fluids. (3) Projections based on disequilibrium temperatures taken at 24 and 36 hours suggest a stabilized maximum temperature of about 260-265 F at 7,450. Maximum observed temperature was 243 F. (4) Geochemically, temperatures at depth should be over 300 F. On the basis of observed temperatures and gradients, 400 F might not be encountered until 12,000 feet at this site. (5) C.H. Stocks 1-A, about one mile northwest, appears to be hotter at comparable depths, and to be better located to penetrate the range-front fault set at drillable depth. (6) Bert Winn No.1 was sited principally on a geoelectrical anomaly in an area of high temperature gradients. With the remote exception of the saline interval at 5,575 to 5,700 feet, no evidence was seen in drilling and logging of any feature that could serve as the source of the geoelectrical anomaly.
Date: December 1, 1980
Creator: McIntyre, J.B. & Koenig, J.B.
Partner: UNT Libraries Government Documents Department

Deflagration Behavior of PBX 9501 at Elevated Temperature and Pressure

Description: We report the deflagration behavior of PBX 9501 at pressures up to 300 MPa and temperatures of 150-180 C where the sample has been held at the test temperature for several hours before ignition. The purpose is to determine the effect on the deflagration behavior of material damage caused by prolonged exposure to high temperature. This conditioning is similar to that experienced by an explosive while it being heated to eventual explosion. The results are made more complicated by the presence of a significant thermal gradient along the sample during the temperature ramp and soak. Three major conclusions are: the presence of nitroplasticizer makes PBX 9501 more thermally sensitive than LX-04 with an inert Viton binder; the deflagration behavior of PBX 9501 is more extreme and more inconsistent than that of LX-04; and something in PBX 9501 causes thermal damage to 'heal' as the deflagration proceeds, resulting in a decelerating deflagration front as it travels along the sample.
Date: April 15, 2008
Creator: Maienschein, J L & Koerner, J G
Partner: UNT Libraries Government Documents Department

Laser heating of solid matter by light pressure-driven shocks

Description: Heating by irradiation of a solid surface in vacuum with 5 x 10{sup 20} W cm{sup -2}, 0.8 ps, 1.05 {micro}m wavelength laser light is studied by x-ray spectroscopy of the K-shell emission from thin layers of Ni, Mo and V. A surface layer is heated to {approx} 5 keV with an axial temperature gradient of 0.6 {micro}m scale length. Images of Ni Ly{sub {alpha}} show the hot region has a {approx} 25 {micro}m diameter, much smaller than {approx} 70 {micro}m region of K{sub {alpha}} emission. 2D particle-in-cell (PIC) simulations suggest that the surface heating is due to a light pressure driven shock.
Date: May 4, 2007
Creator: Akli, K; Hansen, S B; Kemp, A J; Freeman, R R; Beg, F N; Clark, D et al.
Partner: UNT Libraries Government Documents Department

San Emidio Desert Prospect, Washoe and Pershing Counties, Nevada, for Chevron Oil Co., Wells Se-A and SE-B, Temperature depth data, 19 wells

Description: During 1977 Chevron Resources conducted numerous temperature hole programs in the San Emidio Desert Prospect, Nevada. These programs were projected to evaluate recently acquired Fee Land and acreage which could be included in a unit package. The 1977 temperature holes (Map 1) were drilled to a maximum depth of 500 feet with a minimum of 100 feet. Maximum temperature encountered in these holes was 232 F with an average gradient of {approx} 9 F/100 feet (300-400 feet) and {approx} 11 F/100 feet (100-200 feet). In addition, shot holes drilled during the seismic program had temperature pipe installed and were also logged. Table 1 reflects data pertinent to the temperature holes drilled in 1977; in addition, complete temperature gradient plots (Appendix A) and lithology descriptions (Appendix B) are included in this report. Water samples from two temperature holes were collected early in the 1977 program and analyzed by Skyline Laboratories (Appendix C). The results of the estimated base temperature calculations are given.
Date: January 1, 1977
Creator: Kehoe, Mark
Partner: UNT Libraries Government Documents Department

Thermophoresis and Its Thermal Parameters for Aerosol Collection

Description: The particle collection efficiency of a prototype environmental tobacco smoke (ETS) sampler based on the use of thermophoresis is determined by optimizing the operational voltage that determines its thermal gradient. This sampler's heating element was made of three sets of thermophoretic (TP) wires 25mu m in diameter suspended across a channel cut in a printed circuit board and mounted with collection surfaces on both sides. The separation between the heating element and the room temperature collection surface was determined in a numerical simulation based on the Brock-Talbot model. Other thermal parameters of this TP ETS sampler were predicted by the Brock-Talbot model for TP deposition. From the normalized results the optimal collection ratio was expressed in terms of operational voltage and fi lter mass. Prior to the Brock-Talbot model simulation for this sampler, 1.0V was used arbitrarily. The operational voltage was raised to 3.0V, and the collection effi ciency was increased by a factor of fi ve for both theory and experiment.
Date: August 1, 2007
Creator: Huang, Z.; Apte, Michael & Gundel, Lara
Partner: UNT Libraries Government Documents Department

Role of Nucleation and Growth in Two-Phase Microstructure Formation

Description: During the directional solidification of peritectic alloys, a rich variety of two-phase microstructures develop, and the selection process of a specific microstructure is complicated due to the following two considerations. (1) In contrast to many single phase and eutectic microstructures that grow under steady state conditions, two-phase microstructures in a peritectic system often evolve under non-steady-state conditions that can lead to oscillatory microstructures, and (2) the microstructure is often governed by both the nucleation and the competitive growth of the two phases in which repeated nucleation can occur due to the change in the local conditions during growth. In this research, experimental studies in the Sn-Cd system were designed to isolate the effects of nucleation and competitive growth on the dynamics of complex microstructure formation. Experiments were carried out in capillary samples to obtain diffusive growth conditions so that the results can be analyzed quantitatively. At high thermal gradient and low velocity, oscillatory microstructures were observed in which repeated nucleation of the two phases was observed at the wall-solid-liquid junction. Quantitative measurements of nucleation undercooling were obtained for both the primary and the peritectic phase nucleation, and three different ampoule materials were used to examine the effect of different contact angles at the wall on nucleation undercooling. Nucleation undercooling for each phase was found to be very small, and the experimental undercooling values were orders of magnitude smaller than that predicted by the classical theory of nucleation. A new nucleation mechanism is proposed in which the clusters of atoms at the wall ahead of the interface can become a critical nucleus when the cluster encounters the triple junction. Once the nucleation of a new phase occurs, the microstructure is found to be controlled by the relative growth of the two phases that give rise to different oscillatory microstructures that depend ...
Date: May 1, 2008
Creator: Shin, Jong Ho
Partner: UNT Libraries Government Documents Department

Summary of results from a thermal gradient survey of the San Emidio wells Washoe County, Nevada, for Chevron Oil Co., Wells SE-A and SE-B, Project No. 76.112

Description: This summary describes the results obtained from a temperature gradient survey of the San Emidio wells drilled in Washoe County, Nevada. The temperature gradient survey was performed during the month of July, 1976, by Geonomics, Inc., for the Chevron Oil Company. The approximate location of the survey is shown in Figure 1. A total of two holes were drilled with locations plotted on Figure 2.
Date: August 1, 1976
Creator: Katzenstein, A.M. & Sanyai, S.K.
Partner: UNT Libraries Government Documents Department

An Expression for the Temperature Gradient in Chaotic Fields

Description: A coordinate system adapted to the invariant structures of chaotic magnetic fields is constructed. The coordinates are based on a set of ghost-surfaces, defined via an action-gradient flow between the minimax and minimizing periodic orbits. The construction of the chaotic coordinates allows an expression describing the temperature gradient across a chaotic magnetic field to be derived. The results are in close agreement with a numerical calculation.
Date: December 22, 2008
Creator: Hudson, S.R.
Partner: UNT Libraries Government Documents Department

Radial Particle Flux in the SOL of DIII-D During ELMing H-Mode

Description: The radial particle flux in the scrape-off-layer (SOL) during ELMing H-mode is examined in DIII-D as a function of density. The global radial particle flux in the outboard far SOL is determined by a window frame technique. Between ELMs the outboard far SOL particle flux increases strongly with density but remains similar to the particle flux across the separatrix as estimated by the pedestal density and temperature gradients. At low density the steep density gradient of the pedestal extends up to 2 cm outside the separatrix. At high density the density gradient flattens just outside the separatrix making this region critical for assessment of the far SOL particle flux. During ELMs the far SOL particle flux becomes localized to the outboard midplane and the assumptions for the window frame analysis break down. Implications for scaling of main chamber wall particle flux and pedestal fueling are explored.
Date: June 1, 2006
Creator: Leonard, A W; Boedo, J A; Groth, M; Lipschultz, B L; Porter, G D; Rudakov, D L et al.
Partner: UNT Libraries Government Documents Department

Thermal Tests of Undulator Quad

Description: Running at the nominal temperature, the undulator quadrupole has a several degree temperature increase. This note describes the test used to determine the effect on the undulator integrals from the temperature gradient caused by the heat from the quadrupole conducting down the beam pipe. The undulator quadrupoles running at their nominal current of 4 amps heat up approximately 4 degrees Celsius; this magnet in turn heats up the beampipe which goes into the undulator. The heating ends up introducing a thermal gradient across the undulator which causes small changes in the magnetic field of the heated poles. By measuring the temperature change in the poles we can model the effects on the field and determine what the magnetic errors will be.
Date: November 18, 2010
Creator: Fisher, Andrew; /SLAC & ,
Partner: UNT Libraries Government Documents Department