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Investigation of centrifugal compressor operated as a centripetal refrigeration turbine

Description: Report presenting testing of a centrifugal compressor from a production-type turbojet engine, which was successfully operated as a centripetal refrigeration turbine over a range of rotor speed, inlet pressure, and pressure ratio for full admission. The performance results indicated that partial admission was found to be the most efficient method of turbine control, but throttling at the turbine inlet was easy to apply. When nozzles are used, they should have erosion-resistant surfaces to minimize erosion effects.
Date: December 4, 1950
Creator: Rebeske, John J., Jr.; Parisen, Richard B. & Schum, Harold J.
Partner: UNT Libraries Government Documents Department

Ice Houses and the Use of Ice on the Dairy Farm

Description: Report discussing the use of ice to prevent dairy products from spoiling. Icehouses and ice tanks are considered the most effective means of keeping dairy products cool, and instructions for setting up ice tanks and building ice houses are included.
Date: 1915
Creator: Bowen, John T. & Lambert, Guy M.
Partner: UNT Libraries Government Documents Department

Proposed Methodology for LEED Baseline Refrigeration Modeling (Presentation)

Description: This PowerPoint presentation summarizes a proposed methodology for LEED baseline refrigeration modeling. The presentation discusses why refrigeration modeling is important, the inputs of energy models, resources, reference building model cases, baseline model highlights, example savings calculations and results.
Date: February 1, 2011
Creator: Deru, M.
Partner: UNT Libraries Government Documents Department

EHD enhancement of boiling/condensation, heat transfer of alternate refrigerants. Final Report for 1993-1999

Description: The goal was to address the feasibility of frost control by the EHD technique for operating conditions and geometries of significance to refrigeration. The objective of the experimental investigation was to demonstrate by experiment the feasibility of the EHD technique for control of frost on a cold surface under operating conditions of direct significance to refrigeration applications.
Date: September 1, 1999
Creator: Ohadi, M. M.
Partner: UNT Libraries Government Documents Department

Evaluation of Industrial Magnetic Heat Pump/Refrigerator Concepts that Utilize Superconducting Magnets

Description: This report provides a preliminary assessment of some magnetic heat pump (MHP)/refrigeration concepts for cryogen liquefaction and other industrial applications. The study was performed by Astronautics Corporation of America for Argonne National Laboratory under the sponsorship of the U.S. Department of Energy.
Date: June 1989
Creator: Waynert, J. A.; DeGregoria, A. J.; Foster, R. W. & Barclay, J. A.
Partner: UNT Libraries Government Documents Department

Chemical Safety: Alert

Description: This is a chemical safety alert on the hazards of ammonia releases at ammonia refrigeration facilities.
Date: August 2001
Creator: United States. Environmental Protection Agency. Office of Solid Waste and Emergency Response.
Partner: UNT Libraries Government Documents Department


Description: The main challenge to build the cryogenic system for the Beijing Electron-Positron Collider Upgrade is to accommodate the strong differences among three types of superconducting devices with regard to their structure, location, as well as the cryogenic operating requirement. Three kinds of cooling methods are applied in the overall cryogenic system, saturated liquid helium cooling for the SRF cavities, single-phase helium cooling for the SCQ magnets, and two-phase helium cooling for the SSM solenoid. The optimization for the BEPCII cryogenic system was carried out by using a large-scale computational simulation package. This paper presents thermal parameters and numerical analyses for the BEPCII cryogenic system.
Date: September 22, 2003
Creator: WANG,L. JIA,L. X. DU,H. P. YANG,G. D.
Partner: UNT Libraries Government Documents Department

Novel materials for laser refrigeration

Description: The status of optical refrigeration of rare-earth-doped solids is reviewed, and the various factors that limit the performance of current laser-cooling materials are discussed. Efficient optical refrigeration is possible in materials for which {Dirac_h}{omega}{sub max} < E{sub p}/8, where {Dirac_h}{omega}{sub max} is the maximum phonon energy of the host material and E{sub p} is the pump energy of the rare-earth dopant. Transition-metal and OH{sup -}impurities at levels >100 ppb are believed to be the main factors for the limited laser-cooling performance in current materials. The many components of doped ZBLAN glass pose particular processing challenges. Binary fluoride glasses such as YF{sub 3}-LiF are considered as alternatives to ZBLAN. The crystalline system KPb{sub 2}CI{sub 5} :Dy{sup 3+} is identified as a prime candidate for high-efficiency laser cooling.
Date: January 1, 2009
Creator: Hehlen, Markus P
Partner: UNT Libraries Government Documents Department

Design and construction of a 425-MHz cryogenic (20K) two-cell DTL (drift-tube linac) sparker

Description: A two-cell 425-MHz drift-tube linac (DTL) ''sparker'' for operation at 20 K has been designed and constructed to operate at >2 Kilpatrick accelerating voltage while transporting an H/sup /minus// 5-MeV beam at currents up to 100 mA. Permanent-magnet quadrupole (PMQ) assemblies are installed in the input/output beam-transport system and in the cryogenically cooled cavity drift-tube and two half-cells. The cavity, cooled by a 700-W cold-helium gas refrigerator, is mounted inside a superinsulated high-vacuum chamber that is evacuated by a 360-/ell//s turbomolecular vacuum-pump system. The cavity components (slug tuner, post coupler, drive loop) are fabricated from electropolished OFHC possessing a residual resistivity ratio of >200. The rf contacts for the cavity end walls are copper-plated Inconel X-750 C-seals. The drift-tube stem, post-coupler stem, and slug tuner use gold-plated beryllium/copper Multilam bands rf contacts. Initial experiments at 20 K have shown a cavity Q enhancement of 4-5. The experimental program includes characterization of the rf cavity beam loading, engineering design and construction, and thermal system response. 11 refs., 2 figs.
Date: January 1, 1988
Creator: Wilson, N.G.; Bolme, G.O. & Kalash, K.
Partner: UNT Libraries Government Documents Department

The Prospects of Alternatives to Vapor Compression Technology for Space Cooling and Food Refrigeration Applications

Description: Five alternatives to vapor compression technology were qualitatively evaluated to determine their prospects for being better than vapor compression for space cooling and food refrigeration applications. The results of the assessment are summarized in the report. Overall, thermoacoustic and magnetic technologies were judged to have the best prospects for competing with vapor compression technology, with thermotunneling, thermoelectric, and thermionic technologies trailing behind in that order.
Date: March 31, 2010
Creator: Brown, Daryl R.; Dirks, James A.; Fernandez, Nicholas & Stout, Tyson E.
Partner: UNT Libraries Government Documents Department

Elastohydrodynamic Lubrication with Polyolester Lubricants and HFC Refrigerants, Final Report, Volume 1

Description: The objective of this study was to investigate the film formation properties of refrigeration lubricants using the ultrathin film elastohydrodynamic (EHD) interferometry technique and to study the effects of refrigerants on film formation. Film thickness measurements were conducted as a function of lubricant viscosity, speed, temperature, and refrigerant concentration. Based on the EHD film thickness data, effective pressure-viscosity coefficients were calculated for the test fluids at different temperatures and the effects of refrigerants on pressure-viscosity properties were investigated.
Date: April 1, 1999
Creator: Gunsel, Selda & Pozebanchuk, Michael
Partner: UNT Libraries Government Documents Department

United States Department of Energy large commercial absorption chiller development program

Description: The US Department of Energy (DOE) is working with partners from the gas cooling industry to improve energy efficiency and US competitiveness by using advanced absorption technologies that eliminate the use of chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs), refrigerants that contribute to ozone depletion and global warming. Absorption cooling uses natural gas as the heat source, which produces much lower NO{sub x} emissions than oil- or coal-generated electricity. Gas-fired chillers also have the advantage of helping reduce peak electrical usage during summer months. To assist industry in developing advanced absorption cooling technologies, DOE sponsors the Large Commercial Chiller Development Program. The goal of the program is to improve chiller cooling efficiency by 30--50% compared with the best currently available absorption systems.
Date: November 1, 1998
Creator: Garland, P.W.; DeVault, R.C. & Zaltash, A.
Partner: UNT Libraries Government Documents Department

Experimental and cost analyses of a one kilowatt-hour/day domestic refrigerator-freezer

Description: Over the past ten years, government regulations for energy standards, coupled with the utility industry`s promotion of energy-efficient appliances, have prompted appliance manufacturers to reduce energy consumption in refrigerator-freezers by approximately 40%. Global concerns over ozone depletion have also required the appliance industry to eliminate CFC-12 and CFC-11 while concurrently improving energy efficiency to reduce greenhouse emissions. In response to expected future regulations that will be more stringent, several design options were investigated for improving the energy efficiency of a conventionally designed, domestic refrigerator-freezer. The options, such as cabinet and door insulation improvements and a high-efficiency compressor were incorporated into a prototype refrigerator-freezer cabinet and refrigeration system. Baseline energy consumption of the original 1996 production refrigerator-freezer, along with cabinet heat load and compressor calorimeter test results, were extensively documented to provide a firm basis for experimentally measured energy savings. The goal for the project was to achieve an energy consumption that is 50% below in 1993 National Appliance Energy Conservation Act (NAECA) standard for 20 ft{sup 3} (570 l) units. Based on discussions with manufacturers to determine the most promising energy-saving options, a laboratory prototype was fabricated and tested to experimentally verify the energy consumption of a unit with vacuum insulation around the freezer, increased door thicknesses, a high-efficiency compressor, a low wattage condenser fan, a larger counterflow evaporator, and adaptive defrost control.
Date: May 1, 1997
Creator: Vineyard, E.A. & Sand, J.R.
Partner: UNT Libraries Government Documents Department

Compatibility of refrigerants and lubricants with electrical sheet insulation under retrofit conditions

Description: To determine whether exposure to the original refrigerant/mineral oil would affect compatibility of sheet insulation with alternative refrigerant/lubricant after retrofit, sheet insulation was exposed at elevated temperature to the original refrigerant and mineral oil for 500 hours, followed by exposure to the alternative refrigerant and lubricant for 500 hours. Most of the sheet insulation materials exposed to the alternative refrigerant and lubricant (after an initial exposure to the original refrigerant and mineral oil) appeared to be compatible with the alternative refrigerant and lubricant. The only concern was delamination and blistering of the sheet insulation containing Nomex, especially after removal of absorbed refrigerant at high temperature. This was attributed to incompatibility of the adhesive and not to the Nomex itself. Embrittlement of the polyethylene terephthalate (PET) sheet was initially observed, but 2048 subsequent tests under extremely dry conditions showed that embrittlement of the PET materials was attributed to moisture present during the exposure.
Date: November 1, 1996
Creator: Doerr, R.G. & Waite, T.D.
Partner: UNT Libraries Government Documents Department

Wind-electric icemaking project: Analysis and dynamometer testing. Volume 2

Description: The wind/hybrid systems group at the National Renewable Energy Laboratory has been researching the most practical and cost-effective methods for producing ice from off-grid wind-electric power systems. The first phase of the project, conducted in 1993--1994, included full-scale dynamometer and field testing of two different electric ice makers directly connected to a permanent magnet alternator. The results of that phase were encouraging and the second phase of the project was launched in which steady-state and dynamic numerical models of these systems were developed and experimentally validated. The third phase of the project was the dynamometer testing of the North Star ice maker, which is powered by a 12-kilowatt Bergey Windpower Company, Inc., alternator. This report describes both the second and third project phases. Also included are detailed economic analyses and a discussion of the future prospects of wind-electric ice-making systems. The main report is contained in Volume 1. Volume 2 consists of the report appendices, which include the actual computer programs used in the analysis and the detailed test results.
Date: July 1998
Creator: Holz, R.; Gervorgian, V.; Drouilhet, S. & Muljadi, E.
Partner: UNT Libraries Government Documents Department

Development of vehicle magnetic air conditioner (VMAC) technology. Final report

Description: The objective of Phase I was to explore the feasibility of the development of a new solid state refrigeration technology - magnetic refrigeration - in order to reduce power consumption of a vehicle air conditioner by 30%. The feasibility study was performed at Iowa State University (ISU) together with Astronautics Corporation of America Technology Center (ACATC), Madison, WI, through a subcontract with ISU.
Date: August 28, 2001
Creator: Gschneidner, Karl A., Jr.; Pecharsky, V.K.; Jiles, David & Zimm, Carl B.
Partner: UNT Libraries Government Documents Department

High efficiency, high capacity cooling and refrigeration. Semi-annual report for the period May-October 1999

Description: Tasks 1 through 3 (identify candidate refrigerants, construct bench-top test device, test candidate refrigerants in the bench-top device) are complete. The project is on budget and on schedule. Significant positive results have been obtained.
Date: October 1, 1999
Creator: McCullough, Edward T.; Dhooge, Patrick M. & Nimitz, J. S.
Partner: UNT Libraries Government Documents Department

Criteria for the SSC helium refrigerator

Description: This report discusses the following criteria for the SSC helium refrigerator: Cryogenic system description; required services for the magnet system; transport of cryogenic fluids around the rings; steady state loads; magnet system cooldown; helium storage facility; refrigerator requirements after a quench; refrigerator capacity; refrigerator redundancy; future expandability; utilities; and description of refrigeration plant studied by the CDG.
Date: March 1, 1987
Creator: VanderArend, P.
Partner: UNT Libraries Government Documents Department

Thermally activated heat pumps

Description: This article describes research to develop efficient gas-fired heat pumps heat and cool buildings without CFCs. Space heating and cooling use 46% of all energy consumed in US buildings. Air-conditioning is the single leading cause of peak demand for electricity and is a major user of chlorofluorocarbons (CFCs). Advanced energy conversion technology can save 50% of this energy and eliminate CFCs completely. Besides saving energy, advanced systems substantially reduce emissions of carbon dioxide (a greenhouse gas), sulfur dioxide, and nitrogen oxides, which contribute to smog and acid rain. These emissions result from the burning of fossil fuels used to generate electricity. The Office of Building Technologies (OBT) of the US Department of Energy supports private industry`s efforts to improve energy efficiency and increase the use of renewable energy in buildings. To help industry, OBT, through the Oak Ridge National Laboratory, is currently working on thermally activated heat pumps. OBT has selected the following absorption heat pump systems to develop: generator-absorber heat-exchange (GAX) cycle for heating-dominated applications in residential and light commercial buildings; double-condenser-coupled (DCC) cycle for commercial buildings. In addition, OBT is developing computer-aided design software for investigating the absorption cycle.
Date: May 1, 1995
Partner: UNT Libraries Government Documents Department