Potential improvements of the Coefficient of Performance (COP) were investigated for R-407C at cooling and heating conditions of a residential heat pump. The study used CYCLE-11, a semi-theoretical vapor-compression cycle model, which was upgraded to simulate cross-flow, counter-flow, and parallel-flow evaporator and condenser with no restrictions on specifying superheated vapor and subcooled l...

R502 is due to be banned in the near future, and ti)e need for an immediately available and easy-to-use alternative is becoming more and more urgent. Retrofitting refrigerating units can prove easier and less expensive if the mineral or alkylbenzene lubricants usually adopted with R502 have a certain miscibility in the drop-in mixtures. This paper examines the near-azeotropic mixture Rl43a/290/...

Per Lundqvist Dr., Lars Herbe M.Sc, The Royal Institute ofTechnology, Dept. of Energy Technology, S-100 44, Stockholm, Sweden Fax: +46 8 20 30 07 Tel: +46 8 790 74 52 Email: [email protected] There are several important issues when dealing with new refrigerants in a retrofit situation. This paper is however restricted to system performance and a discussion of methods suitable to determine ...

Madeleine R. Johnson AGMC/MAEL 813 Irving Wick Drive West Newark AFB, Ohio 43057-5149 This paper describes the initial results of a refrigerant retrofit project at the Aerospace Guidance and Metrology Center (AGMC) at Newark Air Force Base, Ohio. The objective is to convert selected types of test equipment to properly operate on hydrofluorocarbon (HFC) alternative refrigerants, having no ozone ...

Application ofHFC refrigerants for air conditioners and refrigerators has been studied. Development of a common oil, based on a combination ofpolyolester and additive packages, is aimed for R-22 and HFCs refrigerants, and the evaluation tests of reliability in compressor and refrigeration system brought about good results. This refrigeration lubricant is already partly commercialized in HFC ref...

Refrigeration oil and other materials used with refrigerant for refrigerators or air conditioners should have thermal and chemical stability to maintain the system reliability. Some kinds of synthetic oil are used for alternative refrigerant, HFC’s and hydrolysis, material compatibility, and low-temperature extraction of contaminant or sludge are important subjects. Much more numbers and times ...

Vapor pressures in the range of 256 to 331 K and saturated liquid and vapor densities from 315 to 331 K have been measured for difluoromethane (HFC-32) on the saturation line by means of variable volume and static experimental methods. Our results have been combined with literature values, and on the basis of all the measurements, accurate analytical correlations for saturated liquid and vapor ...