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SBIR Grant: œNo-Vibration Agile Cryogenic Optical Refrigerator

Description: Optical refrigeration is currently the only all-solid-state cryocooling technology that has been demonstrated. Optical cryocoolers are devices that use laser light to cool small crystal or glass cooling elements. The cooling element absorbs the laser light and reradiates it at higher energy, an example of anti-Stokes fluorescence. The dif-ference between the energy of the outgoing and incoming light comes from the thermal energy of the cooling element, which in turn becomes colder. Entitled “No-Vibration Agile Cryocoolers using Optical Refrigeration,” this Phase I proposal directly addressed the continued development of the optical refrigerator components necessary to transition this scientific breakthrough into National Nu-clear Security Administration (NNSA) sensor applications in line with the objectives of topic 50b. ThermoDynamic Films LLC (TDF), in collaboration with the University of New Mexico (UNM), cooled an optical-refrigerator cooling element comprised of an ytterbium-doped yttrium lithium fluoride (Yb:YLF) crystal from room tempera-ture to 123 K with about 2% efficiency. This is the world record in optical refrigera-tion and an important step toward revolutionizing cryogenic systems for sensor ap-plications. During this period, they also designed and analyzed the crucial elements of a prototype optical refrigerator including the thermal link that connects the cool-ing element with the load.
Date: April 9, 2013
Creator: Epstein, Richard
Partner: UNT Libraries Government Documents Department
open access

Antiproton stacking in the Recycler

Description: Possibilities to accumulate antiprotons in the Recycler are considered for three different cases: with current stochastic cooling, with upgraded stochastic cooling and with electron cooling. With stochastic cooling only, even upgraded, Recycler looks hardly useful. However, with electron cooling at its goal parameters and reasonably good vacuum in the Recycler, this machine would be efficient.
Date: June 23, 2003
Creator: Burov, Alexey
Partner: UNT Libraries Government Documents Department
open access

"Hot" for Warm Water Cooling

Description: Liquid cooling is key to reducing energy consumption for this generation of supercomputers and remains on the roadmap for the foreseeable future. This is because the heat capacity of liquids is orders of magnitude larger than that of air and once heat has been transferred to a liquid, it can be removed from the datacenter efficiently. The transition from air to liquid cooling is an inflection point providing an opportunity to work collectively to set guidelines for facilitating the energy efficiency of liquid-cooled High Performance Computing (HPC) facilities and systems. The vision is to use non-compressor-based cooling, to facilitate heat re-use, and thereby build solutions that are more energy-efficient, less carbon intensive and more cost effective than their air-cooled predecessors. The Energy Efficient HPC Working Group is developing guidelines for warmer liquid-cooling temperatures in order to standardize facility and HPC equipment, and provide more opportunity for reuse of waste heat. This report describes the development of those guidelines.
Date: August 26, 2011
Creator: Corporation, IBM; Group, Energy Efficient HPC Working; Corporation, Hewlett Packard; SGI; Inc., Cray; Corporation, Intel et al.
Partner: UNT Libraries Government Documents Department
open access

Passive cooling program element. [Skytherm system]

Description: An outline of the Passive Cooling R and D program element is presented with significant technical achievements obtained during FY 1978. Passive cooling mechanisms are enumerated and a survey of ongoing projects is made in the areas of cooling resource assessment and system development. Results anticipated within the next fiscal year are discussed and the direction of the R and D effort is indicated. Passive cooling system development has centered primarily about the Skytherm system. Two projects are underway to construct such systems in regions having a higher cooling load than the original Skytherm site at Atascadero, California. Component development and commercialization studies are major goals of these two projects and a third project at Atascadero. A two-story passive cooling test module has been built to study radiative, evaporative and convective cooling effects in a structure making use of the thermosiphon principle, but not equipped with a roof pond.
Date: September 1, 1978
Creator: Wahlig, M. & Martin, M.
Partner: UNT Libraries Government Documents Department
open access

Investigation of Internal Film Cooling of 1000-Pound-Thrust Liquid-Ammonia - Liquid-Oxygen Rocket-Engine Combustion Chamber

Description: Memorandum presenting an investigation of internal film cooling of the combustion chamber of a 1000-pound-thrust liquid-ammonia-liquid-oxygen rocket engine. The three coolants studied were water, ethyl alcohol, and liquid ammonia. Results regarding heat-transfer results, liquid film-cooled length, correlation of heat-transfer data, and effect of film cooling on performance are provided.
Date: July 17, 1951
Creator: Morrell, Gerald
Partner: UNT Libraries Government Documents Department
open access

Performance characteristics of aircraft cooling ejectors having short cylindrical shrouds

Description: The factors affecting the performance of ejector suitable for aircraft cooling are investigated theoretically and experimentally. The investigation covers a range of shroud-to-nozzle diameter ratios from 1.1 to 1.6, of shroud lengths from 0.2 to 2.28 nozzle diameters, of secondary-to-primary weight-flow ratios from 0 to 0.12, and of ambient-to-nozzle pressure ratios from 0.7 to 0.06. The results of a simplified theoretical analysis based on each type of flow are in good agreement with those experimentally obtained.
Date: May 22, 1951
Creator: Kochendorfer, Fred D. & Rousso, Morris D.
Partner: UNT Libraries Government Documents Department
open access

High-Altitude Cooling 1: Resume of the Cooling Problem

Description: Report presenting a paper in a series about the cooling of aircraft-engine installations with special reference to the difficulties of cooling at high altitudes. This particular paper discusses the properties of NACA standard air and Army summer air, with corresponding stagnation conditions for a range of flight speed, as summarized in tables and figures.
Date: September 1944
Creator: Silverstein, Abe
Partner: UNT Libraries Government Documents Department
open access

Analysis of climatic conditions and preliminary assessment of alternative cooling strategies for houses in California transition climate zones

Description: This is a preliminary scoping study done as part of the {open_quotes}Alternatives to Compressive Cooling in California Transition Climates{close_quotes} project, which has the goal of demonstrating that houses in the transitional areas between the coast and the Central Valley of California do not require air-conditioning if they are properly designed and operated. The first part of this report analyzes the climate conditions within the transitional areas, with emphasis on design rather than seasonal conditions. Transitional climates are found to be milder but more variable than those further inland. The design temperatures under the most stringent design criteria, e.g. 0.1 % annual, are similar to those in the Valley, but significantly lower under more relaxed design criteria, e.g., 2% annual frequency. Transition climates also have large day-night temperature swings, indicating significant potential for night cooling, and wet-bulb depressions in excess of 25 F, indicating good potential for evaporative cooling. The second part of the report is a preliminary assessment using DOE-2 computer simulations of the effectiveness of alternative cooling and control strategies in improving indoor comfort conditions in two conventional Title-24 houses modeled in various transition climate locations. The cooling measures studied include increased insulation, light colors, low-emissivity glazing, window overhangs, and exposed floor slab. The control strategies studied include natural and mechanical ventilation, and direct and two-stage evaporative cooling. The results indicate the cooling strategies all have limited effectiveness, and need to be combined to produce significant improvements in indoor comfort. Natural and forced ventilation provide similar improvements in indoor conditions, but during peak cooling periods, these will still be above the comfort zone. Two-stage evaporative coolers can maintain indoor comfort at all hours, but not so direct evaporative coolers.
Date: July 1, 1995
Creator: Huang, Y. J. & Zhang, H.
Partner: UNT Libraries Government Documents Department
open access

Analytical comparison of turbine-blade cooling systems designed for a turbojet engine operating at supersonic speed and high altitude 2: air-cooling systems

Description: Report presenting an investigation of the influence of high-altitude supersonic flight on the operation and effectiveness of turbine-blade air- and liquid-cooling systems for turbojet application in guided missiles and supersonic interceptor aircraft. Results regarding the coolant passage heat-transfer-coefficients, nonrefrigerated air-cooling-system characteristics, and refrigerated-air-cooling-system characteristics are provided.
Date: February 19, 1953
Creator: Schramm, Wilson B.; Arne, Vernon L. & Nachtigall, Alfred J.
Partner: UNT Libraries Government Documents Department
open access

Operating Temperatures of a Sodium-Cooled Exhaust Valve as Measured by a Thermocouple

Description: Report presents the results of a thermocouple installed in the crown of a sodium-cooled exhaust valve. The valve was tested in an air-cooled engine cylinder and valve temperatures under various engine operating conditions were determined. A temperature of 1337 degrees F. was observed at a fuel-air ratio of 0.064, a brake mean effective pressure of 179 pounds per square inch, and an engine speed of 2000 r.p.m.
Date: 1943
Creator: Sanders, J. C.; Wilsted, H. D. & Mulcahy, B. A.
Partner: UNT Libraries Government Documents Department
open access

Internal-liquid-film-cooling experiments with air-stream temperatures to 2000 degrees F. in 2- and 4-inch-diameter horizontal tubes

Description: Report presents the results of an investigation conducted to determine the effectiveness of liquid-cooling films on the inner surfaces of tubes containing flowing hot air. Experiments were made in 2- and 4-inch-diameter straight metal tubes with air flows at temperatures from 600 degrees to 2000 degrees F. and diameter Reynolds numbers from 2.2 to 14 x 10(5). The film coolant, water, was injected around the circumference at a single axial position on the tubes at flow rates from 0.02 to .24 pound per second per foot of tube circumference (0.8 to 12 percent of the air flow). Liquid-coolant films were established and maintained around and along the tube wall in concurrent flow with the hot air. The results indicated that, in order to film cool a given surface area with as little coolant flow as possible, it may be necessary to limit the flow of coolant introduced at a single axial position and to introduce it at several axial positions. The flow rate of inert coolant required to maintain liquid-film cooling over a given area of tube surface can be estimated when the gas-flow conditions are known by means of a generalized plot of the film-cooling data.
Date: May 27, 1952
Creator: Kinney, George R.; Abramson, Andrew E. & Sloop, John L.
Partner: UNT Libraries Government Documents Department
open access

Cooling in a compound bucket

Description: Electron cooling in the Fermilab Recycler ring is found to create correlation between longitudinal and transverse tails of the antiproton distribution. By separating the core of the beam from the tail and cooling the tail using 'gated' stochastic cooling while applying electron cooling on the entire beam, one may be able to significantly increase the overall cooling rate. In this paper, we describe the procedure and first experimental results.
Date: September 1, 2007
Creator: Shemyakin, A.; Bhat, C.; Broemmelsiek, D.; Burov, A.; Hu, M. & /Fermilab
Partner: UNT Libraries Government Documents Department
open access

Effects of internal configuration on afterburner shell temperatures

Description: From Summary: "A brief investigation was conducted in the altitude wind tunnel to determine the extent to which the afterburner shell cooling problem could be alleviated by internal configuration changes. Data were obtained with and without a cooling liner installed and for variations in the radial fuel distribution and in the radial distribution in flame-seat area. Consideration is given to the effects on both shell temperature and afterburner performance."
Date: January 8, 1952
Creator: Conrad, E. William & Jansen, Emmert T.
Partner: UNT Libraries Government Documents Department
open access

Flight and Test-Stand Investigation of High-Performance Fuels in Double-Row Radial Air-Cooled Engines 1: Determination of Cooling Characteristics of Flight Engine

Description: Report discussing the cooling characteristics of a 14-cylinder double-row radial air-cooled engine in a four-engine airplane. The effects of charge-air flow, cooling-air pressure drop, and fuel-air ratio on the cooling characteristics were measured separately. The cooling equation, rear middle-barrel temperature, cooling-limited manifold pressure, and maximum cruising power versus temperature-limited power are described.
Date: December 20, 1944
Creator: Blackman, Calvin C.; White, H. Jack & Pragliola, Philip C.
Partner: UNT Libraries Government Documents Department
open access

Gas-to-blade heat-transfer coefficients and turbine heat-rejection rates for a range of one-spool cooled-turbine engine designs

Description: Report presenting gas-to-blade heat-transfer coefficients and turbine heat-rejection rates obtained for a wide range of one-spool turbojet engine designs believed to be representative of engines that will employ turbine cooling. The values of heat-transfer coefficient and heat-rejection rates are applicable to both liquid- and air-cooled turbines. Results regarding the heat-transfer coefficients and heat-rejection rates for turbojet engine designs, total heat-rejection rates for various turbojet engine and flight conditions, and heat-transfer coefficients and heat-rejection rates for turboprop engine design are provided.
Date: May 14, 1956
Creator: Slone, Henry O. & Esgar, Jack B.
Partner: UNT Libraries Government Documents Department
open access

Blower Cooling of Finned Cylinders

Description: "Several electrically heated finned steel cylinders enclosed in jackets were cooled by air from a blower. The effect of the air conditions and fin dimensions on the average surface heat-transfer coefficient q and the power required to force the air around the cylinders were determined. Tests were conducted at air velocities between the fins from 10 to 130 miles per hour and at specific weights of the air varying from 0.046 to 0.074 pound per cubic foot. The fin dimensions of the cylinders covered a range in pitches from 0.057 to 0.25 inch average fin thicknesses from 0.035 to 0.04 inch, and fin widths from 0.67 to 1.22 inches" (p. 269).
Date: November 14, 1936
Creator: Schey, Oscar W. & Ellerbrock, Herman H., Jr.
Partner: UNT Libraries Government Documents Department
open access

Effect of Air Cooling of Turbine Disk on Power and Efficiency of Turbine from Turbo Engineering Corporation TT13-18 Turbosupercharger

Description: "An investigation was conducted to determine the effect of turbine-disk cooling with air on the efficiency and the power output of the radial-flow turbine from the Turbo Engineering Corporation TT13-18 turbosupercharger. The turbine was operated at a constant range of ratios of turbine-inlet total pressure to turbine-outlet static pressure of 1,5 and 2.0, turbine-inlet total pressure of 30 inches mercury absolute, turbine-inlet total temperature of 12000 to 20000 R, and rotor speeds of 6000 to 22,000 rpm, Over the normal operating range of the turbine, varying the corrected cooling-air weight flow from approximately 0,30 to 0.75 pound per second produced no measurable effect on the corrected turbine shaft horsepower or the turbine shaft adiabatic efficiency" (p. 1).
Date: June 9, 1949
Creator: Berkey, William E.
Partner: UNT Libraries Government Documents Department
open access

Radiative and passive cooling

Description: The two primary accomplishments of the project to date are (1) the construction of a computer model to predict the infrared spectral radiance of the atmosphere under various meteorological conditions of temperature, water vapor profiles, and cloud cover; and (2) the design, testing, and installation of several spectral radiometers for the routine measurement of atmospheric infrared radiance. Emphasis has been placed on the study of the atmospheric radiance which would be absorbed by a thermal radiating surface exposed to the sky because the amount of radiation emmited from a given system can usually be calculated in a straightforward manner.
Date: September 1, 1978
Creator: Martin, M. & Berdahl, P.
Partner: UNT Libraries Government Documents Department
open access

An Analytical Estimation of the Effect of Transpiration Cooling on the Heat-Transfer and Skin-Friction Characteristics of a Compressible, Turbulent Boundary Layer

Description: "An analysis based on mixing-length theory is presented which indicates that surface blowing associated with transpiration cooling systems produce large reductions in both the heat-transfer and skin-friction coefficients for a turbulent boundary layer on a flat plate. The numerical results are restricted to the case of air blowing into air. The effects of blowing are indicated to be similar for high-speed, compressible flow to those for low-speed, incompressible flow" (p. 1).
Date: December 1954
Creator: Rubesin, Morris W.
Partner: UNT Libraries Government Documents Department
open access

Gas-turbine-engine performance when heat from liquid-cooled turbines is rejected ahead of, within, or behind main compressor

Description: Report discussing methods, advantages, and disadvantages of locating rotating heat exchangers ahead of, within, and behind the main engine compressor. Heat rejection should occur at the compressor discharge for best engine performance. Results regarding turbojet-engine performance, turboprop-engine performance, and a comparison of engine performance with liquid- and air-cooling are provided.
Date: May 22, 1956
Creator: Esgar, Jack B. & Slone, Henry O.
Partner: UNT Libraries Government Documents Department
open access

Energy Efficient Electronics Cooling Project

Description: Parker Precision Cooling Business Unit was awarded a Department of Energy grant (DE-EE0000412) to support the DOE-ITP goal of reducing industrial energy intensity and GHG emissions. The project proposed by Precision Cooling was to accelerate the development of a cooling technology for high heat generating electronics components. These components are specifically related to power electronics found in power drives focused on the inverter, converter and transformer modules. The proposed cooling system was expected to simultaneously remove heat from all three of the major modules listed above, while remaining dielectric under all operating conditions. Development of the cooling system to meet specific customer's requirements and constraints not only required a robust system design, but also new components to support long system functionality. Components requiring further development and testing during this project included pumps, fluid couplings, cold plates and condensers. All four of these major categories of components are required in every Precision Cooling system. Not only was design a key area of focus, but the process for manufacturing these components had to be determined and proven through the system development.
Date: February 17, 2012
Creator: O'Shaughnessey, Steve; Louvar, Tim; Trumbower, Mike; Hunnicutt, Jessica & Myers, Neil
Partner: UNT Libraries Government Documents Department
open access

The integration of cryogenic cooling systems with superconducting electronic systems

Description: The need for cryogenic cooling has been critical issue that has kept superconducting electronic devices from reaching the market place. Even though the performance of the superconducting circuit is superior to silicon electronics, the requirement for cryogenic cooling has put the superconducting devices at a disadvantage. This report will talk about the various methods for refrigerating superconducting devices. Cryocooler types will be compared for vibration, efficiency, and cost. Some solutions to specific problems of integrating cryocoolers to superconducting devices are presented.
Date: July 1, 2003
Creator: Green, Michael A.
Partner: UNT Libraries Government Documents Department
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