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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

Refrigeration System Used in Mercury Isotope Collections

Description: From introduction: During 1948, the Isotope Research and Production Division undertook to obtain small quantities of nearly pure mercury isotopes by electromagnetic isotope separation. The possible use of a mercury isotope of even-numbered mass to establish an international standard of length required an isotopic purity greater than 99 per cent. It, became apparent that this degree of separation could only be achieved by preventing random diffusion of un-ionized mercury which otherwise would contaminate the isotope collectors.
Date: December 19, 1949
Creator: Duncan, F. R. & Cobb, W. G.
Partner: UNT Libraries Government Documents Department

ARTI refrigerant database

Description: The Refrigerant Database is an information system on alternative refrigerants, associated lubricants, and their use in air conditioning and refrigeration. It consolidates and facilitates access to property, compatibility, environmental, safety, application and other information. It provides corresponding information on older refrigerants, to assist manufacturers and those using alterative refrigerants, to make comparisons and determine differences. The underlying purpose is to accelerate phase out of chemical compounds of environmental concern. The database provides bibliographic citations and abstracts for publications that may be useful in research and design of air-conditioning and refrigeration equipment. The complete documents are not included, though some may be added at a later date. The database identifies sources of specific information on various refrigerants. It addresses lubricants including alkylbenzene, polyalkylene glycol, polyolester, and other synthetics as well as mineral oils. It also references documents addressing compatibility of refrigerants and lubricants with metals, plastics, elastomers, motor insulation, and other materials used in refrigerant circuits. Incomplete citations or abstracts are provided for some documents. They are included to accelerate availability of the information and will be completed or replaced in future updates.
Date: February 1, 1997
Creator: Calm, J.M.
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

Investigation of flushing and clean-out methods for refrigeration equipment to ensure system compatibility

Description: SECTION 608 of the Clean Air Act Amendments has altered much of the refrigeration service contracting industry. MCLR Project Number 660-52502 was established to examine two areas where the Amendments are influencing contractors to determine if more cost-effective service procedures might be developed. One area where existing service procedures are being revisited involves the removal of contaminants from a refrigeration system after a motor burnout. At one time, a Class 1 substance such as CFC-11 or CFC-113 was used as a flushing agent for cleaning a system after a burnout. On large systems, the compressor was disassembled, and the parts were cleaned using 1,1,1-trichloroethane (TCA) or a TCA-containing mixture. Such alternatives are seldom possible today, as the manufacture of Class 1 substances was banned on January 1, 1996. This report describes processes for mineral oil removal, process alternatives for servicing burnouts, solvents, and laboratory retrofit tests.
Date: April 24, 1996
Creator: Byrne, J.J.; Shows, M. & Abel, M.W.
Partner: UNT Libraries Government Documents Department

Commissioning tools for life-cycle building performance assurance

Description: This paper discusses information systems for building life-cycle performance analysis and the use of computer-based commissioning tools within this context. There are many reasons why buildings do not perform in practice as well as intended at the design stage. One reason is the lack of commissioning. A second reason is that design intent is not well documented, and performance targets for building components and systems are not well specified. Thus, criteria for defining verification and functional tests is unclear. A third reason is that critical information is often lost throughout the building life-cycle, which causes problems such as misunderstanding of operational characteristics and sequences and reduced overall performance. The life-cycle building performance analysis tools project discussed in this paper are focused on chillers and cooling systems.
Date: May 1, 1996
Creator: Piette, M. A.
Partner: UNT Libraries Government Documents Department

Development of a prototype optical refrigerator

Description: This is the final report of a one-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The authors have carried out a range of tasks directed toward the construction and testing of a proof-of-principle optical refrigerator prototype. They procured and tested new cooling elements that are at the heart of an optical refrigerator. The cooling element absorbs pump radiation and then fluoresces with nearly unity quantum efficiency. They constructed and tested a cooling chamber with low thermal emissivity walls that reduces the parasitic heating.
Date: January 1, 1998
Creator: Epstein, R.I.; Edwards, B.C. & Sigel, G.H.
Partner: UNT Libraries Government Documents Department

Engineering analysis of the use of compression refrigerants in the thin polymer icemaker

Description: In previous studies the authors have developed the concept of an ice-making device constructed of thin polymer films, arranged so that when filled with a cold fluid they expand in a set of parallel tubes, on the exterior of which ice forms. When the ice is about one millimeter thick, the cold fluid is removed from the tubes and they collapse, being pulled away from the ice by a vacuum within. The device has been successfully demonstrated in a version where the tubes are filled with a water-ethylene glycol brine. This was followed by an economic assessment which indicated that the device would be even more competitive with existing systems if the compression refrigerant itself were admitted into the polymer film structure on which the ice forms. This report presents an engineering study of such a system, examines the outstanding questions which must still be answered and assesses the potential economics of the system. The authors develop preliminary designs for systems using R-134a and R-C318 as refrigerants which satisfy code requirements. They use standard thermodynamic and heat transfer analysis to determine expected performance for the systems, and combine this with component and assembly cost estimates to prepare life-cycle costs for the two new systems. Comparing them to commercially available systems, they find that these ``polymer evaporator`` systems seem to be completely feasible technically and that if they are successfully demonstrated, they should have substantial economic advantages over existing ice-making devices.
Date: November 1, 1995
Creator: Leigh, R. & Andrews, J.
Partner: UNT Libraries Government Documents Department

Simulation and performance analysis of triple-effect absorption cycles

Description: Performance simulation has been carried out for several triple-effect cycles, designed to improve utilization of high temperature heat sources for absorption systems and capable of substantial performance improvement over equivalent double-effect cycles. The systems investigated include the three-condenser-three-desorber (3C3D) cycle, forming an extension of the conventional double-effect one; the recently proposed Double Condenser Coupled (DCC) cycle which recovers heat from the hot condensate leaving the high temperature condensers and adds it to the lower temperature desorbers; and the dual loop cycle comprising two complete single-effect loops, recovering heat from the condenser and absorber of one loop to the desorber of the other loop and generating a cooling effect in the evaporators of both loops. A modular computer code for simulation of absorption systems was used to investigate the performances of the cycles and compare them on an equivalent basis, by selecting a common reference design and operating condition. Performance simulation was carried out over a range of operating conditions, including some investigation of the influence of the design parameters. Coefficients of performance ranging from 1.27 for the series-flow 3C3D to 1.73 for the parallel-flow DCC have been calculated at the design point. The relative merits and shortcomings of the different cycle configurations has been studied.
Date: August 1, 1993
Creator: Grossman, G.; Wilk, M. & DeVault, R.C.
Partner: UNT Libraries Government Documents Department

Cooling Milk and Cream on the Farm

Description: This bulletin discusses ways for maintaining the cool temperature of milk and cream on the farm in order to prevent bacterial growth. Among the methods discussed are natural ice, surface coolers, cooling tanks, wells and spring water.
Date: 1918
Creator: Gamble, J. A.
Partner: UNT Libraries Government Documents Department

Experimental investigation and model verification for a GAX absorber

Description: In the ammonia-water generator-absorber heat exchange (GAX) absorption heat pump, the heat and mass transfer processes which occur between the generator and absorber are the most crucial in assuring that the heat pump will achieve COPs competitive with those of current technologies. In this study, a model is developed for the heat and mass transfer processes that occur in a counter-current vertical fluted tube absorber (VFTA) with inserts. Correlations for heat and mass transfer in annuli are used to model the processes in the VTA. Experimental data is used to validate the model for three different insert geometries. Comparison of model results with experimental data provides insight into model corrections necessary to bring the model into agreement with the physical phenomena observed in the laboratory.
Date: December 31, 1996
Creator: Palmer, S. C. & Christensen, R. N.
Partner: UNT Libraries Government Documents Department

Model-based performance monitoring: Review of diagnostic methods and chiller case study

Description: The paper commences by reviewing the variety of technical approaches to the problem of detecting and diagnosing faulty operation in order to improve the actual performance of buildings. The review covers manual and automated methods, active testing and passive monitoring, the different classes of models used in fault detection, and methods of diagnosis. The process of model-based fault detection is then illustrated by describing the use of relatively simple empirical models of chiller energy performance to monitor equipment degradation and control problems. The CoolTools(trademark) chiller model identification package is used to fit the DOE-2 chiller model to on-site measurements from a building instrumented with high quality sensors. The need for simple algorithms to reject transient data, detect power surges and identify control problems is discussed, as is the use of energy balance checks to detect sensor problems. The accuracy with which the chiller model can be expected! to predict performance is assessed from the goodness of fit obtained and the implications for fault detection sensitivity and sensor accuracy requirements are discussed. A case study is described in which the model was applied retroactively to high-quality data collected in a San Francisco office building as part of a related project (Piette et al. 1999).
Date: May 1, 2000
Creator: Haves, Phil & Khalsa, Sat Kartar
Partner: UNT Libraries Government Documents Department

Innovative hybrid gas/electric chiller cogeneration. Quarterly technical progress report, April--June, 2000

Description: A meeting was held at Alturdyne's facility in San Diego to discuss project progress. Cliff Carpenter, the NETL Program Manager, attended the meeting. As a result of the meeting, several decisions were made: (1) A General Motors engine would be specified as the prime mover; (2) A Carrier reciprocating compressor would be specified, however a Hitachi screw compressor with an integral oil sump was an interesting candidate if it was available in the right size and for the right price; (3) The motor/generator would provide two functions: as an induction motor and as a synchronous generator. The variable speed, constant frequency feature will not be included in the first generation product; and (4) The refrigerant will be R134-A.
Date: July 1, 2000
Creator: Nowakowski, G.
Partner: UNT Libraries Government Documents Department

ERIP Project No. 670, Nevada Energy Control Systems, Inc.. Final techincal progress report

Description: In order to gauge the effectiveness of the ERIP Project No. 670, Nevada Energy Control Systems, Inc., Grant Number DE-FG01-96EE15670, the Statement of Work must be compared to the achievements by NECSI during the grant period. The following report reflects the aforementioned statement and is coordinated directly with it. The project goal is to gather data and test in order to validate earlier tests of energy savings,safety,reliability and practicality of the NECSI Evaporator Fan Controller in order to fully commercialize and market the product.
Date: February 11, 1998
Creator: Kimber, D.J.
Partner: UNT Libraries Government Documents Department

Impact evaluation of a refrigeration control system installed at Columbia Colstor

Description: This impact evaluation of a computer-based refrigeration control system (RCS) installed at Columbia Colstor in 1990 was conducted for the Bonneville Power Administration (Bonneville) by Pacific Northwest Laboratory (PNL). Concurrent with installing the RCS, the plant was expanded by adding 13,900 m{sup 2} (150,000 ft{sup 2} of storage space and five freeze tunnels. Because this project involved a significant plant expansion, it was ineligible for participation in Bonneville`s Energy $avings Plan Program (E$P). Therefore, a special contract was negotiated. This contract followed, to the extent possible, the E$P principles, adminstrative procedures, and acquisition payment. The primary objectives of this impact evaluation were to assess how much electrical energy is being saved at Columbia Colstor as a result of the Bonneville`s acquisition payment and to determine how much the savings cost Bonneville and the region. The impact of the project was evaluated with a combination of engineering analysis, billing analysis, financial analysis, interviews, and submittal reviews. Based on this impact evaluation, energy savings from this project are expected to be at least 4,130,700 kilowatt-hours/year (kWh/yr), or 0.47 average megawatts (aMW). Because the refrigeration system at Columbia Colstor provides cooling to both the storage rooms and the freeze tunnels, it i not possible to state savings on a per-ton basis. The project cost $287,528 to install, and Columbia Colstor received payment of $180,375 (1991 dollars) from Bonneville for the acquisition of energy savings. The real levelized cost of these energy savings to Bonneville is 4.5 mills/kWh (in 1993 dollars) over the project`s assumed 15-year life, and the real levelized cost to the region is 7.6 mills/kWh in 1993 dollars, not including transmission and distribution effects.
Date: January 1, 1996
Creator: Wrench, L.E.; Spanner, G.E.; Klevgard, L.A. & Sullivan, G.P.
Partner: UNT Libraries Government Documents Department

Investigation of flushing and clean-out methods for refrigeration equipment to ensure system compatibility. Quarterly technical progress report, September 15, 1994--December 15, 1994

Description: Integral Sciences Incorporated is engaged in Part 2 of ARTI Contract No. 660-52502 assessing methods for removing residual mineral oil during retrofits of refrigeration systems. Part 2 focuses on a low side oil separator technique for removing mineral oil from systems being retrofitted to use HFC-134a. The method appears less expensive than the current practice of three lubricant changes with polyolester and may effect an accelerated transition to HFC`s. Testing and method verification has been performed using a refrigeration system located at ISI`s facility. Two HFC-134a field retrofits employing this method will be implemented during the first quarter of 1995. A third and final field retrofit will also be performed to evaluate the advanced method in an R-502 conversion.
Date: July 1, 1995
Creator: Byrne, J.J.
Partner: UNT Libraries Government Documents Department

Heat powered refrigeration compressor. Semi-annual technical report

Description: The objective of this program is to develop and improve the design of previously started prototypes of the Heat Powered Refrigeration Compressor. To build this prototype and ready it for testing by the University of Evansville is another goal. This prototype will be of similar capacity as the compressor that will eventually be commercially produced. This unit can operate on almost any moderate temperature water heat source. This heat source could include such applications as industrial waste heat, solar, wood burning stove, resistance electrical heat produced by a windmill, or even perhaps heat put out by the condenser of another refrigeration system. Work performed in the past four months has consisted of: engineering of HX-1; comparisons of specifications from different companies to ensure state of the art applications of parts for project; coordinating project requirements with machine shop; designing condenser; and partial assembly of HX-1.
Date: January 1, 1981
Creator: Goad, R.R.
Partner: UNT Libraries Government Documents Department

Accelerated screening methods for predicting lubricant performance in refrigerant compressors. Progress report, May 1, 1993--December 31, 1993

Description: As part of an overall testing program to identify more effective bench testers for screening oils for compressors, a comparison is made in this report between data obtained from a Falex specimen tester and those obtained from a high pressure tribometer (HPT). The Falex data were supplied by three compressor manufacturers. These data were mainly obtained by bubbling refrigerants through the oil, whereas, the data from the HPT are based on environmental (temperature and pressure) found in specific contacts in compressors. The same contact geometries and materials are used for both the Falex and the HPT tests. The main purpose of this comparison is to see if the controlled environment and the lower loads used with the HPT produces different rankings than that obtained from the Falex tests. In general, the results obtained from the HPT did not always correlate with each other and those obtained from the Falex tester. These findings are discussed in detail in this report.
Date: January 1, 1994
Creator: Cusano, C.
Partner: UNT Libraries Government Documents Department

Compact heat exchangers for condensation applications: Yesterday, today and tomorrow

Description: Compact heat exchangers are being increasingly considered for condensation applications in the process, cryogenic, aerospace, power and refrigeration industries. In this paper, different configurations available for condensation applications are analyzed and the current state-of-the-knowledge for the design of compact condensers is evaluated. The key technical issues for the design and development of compact heat exchangers for condensation applications are analyzed and major advantages are identified. The experimental data and performance prediction methods reported in the literature are analyzed to evaluate the present design capabilities for different compact heat-exchanger configurations. The design flexibility is evaluated for the development of new condensation applications, including integration with other process equipment.
Date: July 1, 1993
Creator: Panchal, C. B.
Partner: UNT Libraries Government Documents Department

Gas-fired cooling status and trends

Description: The current US heating, ventilating, and air-conditioning (HVAC) market shows that the predictions of a health expansion in this market are attainable in this decade. The HVAC industry`s positive trade balance is widening; their successful hedge against various economic problems (the lack of financial and personnel resources) and their initiative to overcome the technical obstacles (caused by environmental issues) will have a positive, long-term impact. This along with energy availability and a favorable price structure has created a unique opportunity for the gas industry to regain and surpass previous respectable market shares attained with gas cooling technologies. New first generation gas cooling equipment is now entering the US marketplace with bold market predictions for commercial chillers and roof-top units, as well as for residential equipment. The marketing campaign covers a broad base of technical and supporting elements. It is the continued research, education, and training of engineers, architects, dealers, and utility sales personnel that can break the existing and serious barriers to the successful marketing of these cooling equipment products. Research in lowering equipment costs, personnel training, more units in the field, and more utility support in commercialization and deployment activities will guarantee an expansion of the market for the gas industry.
Date: December 31, 1993
Creator: Wurm, J.
Partner: UNT Libraries Government Documents Department

Aging assessment of essential HVAC chillers used in nuclear power plants

Description: The Pacific Northwest Laboratory conducted a comprehensive aging assessment of chillers used in the essential safety air-conditioning systems in nuclear power plants (NPPs). The chillers used, and air-conditioning systems served, vary in design from plant to plant. The review of operating experience indicated that chillers experience aging degradation and failures. The primary aging factors of concern for chillers include vibration, excessive temperatures and pressures, thermal cycling, chemical attack, and poor quality cooling water. The evaluation of Licensee Event Reports (LERs) indicated that about 38% of the failures were primarily related to aging, 55% were partially aging related, and 7% of the failures were unassignable. About 25% of the failures were primarily caused by human, design, procedure, and other errors. The large number of errors is probably directly related to the complexity of chillers and their interfacing systems. Nearly all of the LERs were the result of entering plant Technical Specification Limiting Condition for Operation (LCO) that initiated remedial actions like plant shutdown procedures. The trend for chiller-related LERs has stabilized at about 0.13 LERs per plant year since 1988. Carefully following the vendor procedures and monitoring the equipment can help to minimize and/or eliminate most of the premature failures. Recording equipment performance can be useful for trending analysis. Periodic operation for a few hours on a weekly or monthly basis is useful to remove moisture and non-condensable gases that gradually build up inside the chiller. Chiller pressurization kits are available that will help minimize the amount of moisture and air ingress to low-pressure chillers during standby periods. The assessment of service life condition monitoring of chillers indicated there are many simple to sophisticated methods available that can help in chiller surveillance and monitoring.
Date: September 1, 1996
Creator: Blahnik, D.E. & Camp, T.W.
Partner: UNT Libraries Government Documents Department

Compatibility of refrigerants and lubricants with motor materials under retrofit conditions. Final report, Volume 1

Description: Compatibility tests were conducted on motor materials to determine if exposure to the original refrigerant/mineral oil would affect compatibility of the motor materials after retrofit to the alternative refrigerant/lubricant. The motor materials were 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. Measurements were also taken after 168 and 336 hours. As a control, some samples were exposed to the original refrigerant/mineral oil for a total of 1000 hours. The original refrigerants and the Alternatives tested for retrofit were as follows: Most motor materials exposed to the alternative refrigerant and lubricant (after an initial exposure to the original refrigerant and mineral oil) were 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. This was attributed to solution of the adhesive and not to the Nomex itself. Embrittlement of the polyethylene terephthalate (PET) found in Mylar and Melinex sheet and sleeving insulations was initially observed, but subsequent tests under dry conditions showed that embrittlement of the PET materials was caused by moisture present during the exposure. Compatibility tests of elastomers with R-245ca, retrofitted from R-11 and R-123, showed that the nitrile was compatible with both R-11 and R-245ca, but not with R-123. The neoprene was unsatisfactory because of shrinkage in the R-245ca.
Date: October 1, 1996
Creator: Doerr, R.G. & Waite, T.D.
Partner: UNT Libraries Government Documents Department