MEASUREMENTS OF ABSORPTION RATES OF HFC SINGLE AND BLENDED REFRIGERANTS IN POE OILS

Thermophysical properties of refrigerant/lubricant mixtures play an im portant role in refrigeration and air-conditioning system design. Ther efore it is important to have a good understanding of the mixture comp osition in each system component such as the compressor or evaporator. Because the system operation is dynamic the rates of absorption and d esorption become significant parameters. In this paper measured absorp tion rates of alternative refrigerants in polyolester (POE) oils are r eported. An effective online mass gain method was designed and constru cted to measure the absorption rates and solubility of refrigerants in lubricants. HFC single refrigerants (R-32, R-125, R-134a, and R-143a) , and blended refrigerants (R-404A, R-407C, and R-410A) were tested wi th POE ISO 68 lubricant under various conditions. The experimental res ults showed that, at room temperature, R-134a is the most soluble in P OE ISO 68 oil among all the refrigerants tested at pressures of 239 kP a (20 psig) to 446 kPa (70 psig). Among the blended refrigerants teste d, R-407C was found to be the most soluble at room temperature and pre ssures of 239 kPa and 446 kPa. Experimental solubility data from this new measurement method were compared with data available in the litera ture. Good agreement between the two indicates the feasibility of the new method employed in this investigation.