High Pressure Investigation of Refrigerants HFC245fa, R134a and R123
نویسندگان
چکیده
To increase the power efficiency of refrigeration and air conditioning machinery it would be advantageous to be able to run the compressors without any lubricant added to the refrigerant. Without any added lubricant in the refrigerant it would also be possible to simplify the whole refrigeration machinery by excluding all oil handling systems, and there would not any longer be any risk for oil accumulation in the heat exchangers. To find out if the refrigerants themselves can be used for lubrication purposes in rolling contacts, HFC245fa, R134a and R123 were investigated in a high pressure chamber. There they were compressed to more than one gigapascal (1 GPa) and their compressibility and solidification pressure were measured as well as their shear strength at pressures above the solidification pressure.
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