Solubility, Viscosity and Density of Refrigerant/Lubricant Mixtures

Solubility (vapor pressure) , viscosity and density have been experimentally determined for thirty-five potential refrigeration working fluids. Properties for low refrigerant concentration mixtures (0, 10, 20 and 30 weight percent refrigerant) were determined over the temperature range 0 to IOO•C (32 to 212"F) or to the critical temperature of the refrigerant, and pressure range 0 to 3,500 kPa (0 to 500 psia). High refrigerant concentration data (80, 90 and 100 weight percent refrigerant) is given covering -40 to +40 Celsius in most cases. The working fluids studied include selected combinations ofCFC-12, HCFC-22, HFC-32, HCFC-123, HCFC-124, HFC-125, HFC-134a, HCFC-142b, HFC-143a and HFC-152a with mineral oils, alkylbenzenes, polyolesters (both mixed acid and branched acid) and a polyalkylene glycol. Results are presented in the form of a Daniel Chart, which includes isobaric viscosity curves, and equations. INTRODUCTION Among the concerns associated with non-chlorinated refrigerants and new companion lubricants are lubrication of the compressor with a fluid which is a mixture of lubricant and refrigerant and accomplishing the desired heat transfer objectives with a fluid which is also a mixture oflubricant and refrigerant. Many systems contain an oil sump, in which the lubricating fluid is oil rich with some refrigerant dissolved, and oil migration is present in many, if not all, systems causing the liquid phase of the heat transfer fluid to be a refrigerant rich mixture. This project, which was jointly defined by representatives of industry and government, and was performed under the auspices of the Air Conditioning and Refrigeration Technology Institute, was undertaken to provide basic engineering data applicable to both of these regimes. This paper will focus on the results and observations concerning the similarities and differences between the types oflubricants studied with common refrigerants. Several representative plots are given in this paper to illustrate these points. The reader is strongly encouraged to consult the final report for application specific information. Table 1 below lists the thirty five combinations studied. ACKNOWLEDGMENTS This research is supported, in part, by U. S. Department ofEnergy (Office ofBuilding Technology) grant number DE-FG02-91CE23810: Materials Compatibility and Lubricants Research (MCLR) on CFC-Refrigerant Substitutes. Federal funding supporting this project constitutes 93.67% of allowable costs. Funding from non-government sources supporting this project consists of direct cost sharing of 6.3 3% of allowable costs, and in-kind contributions from the airconditioning and refrigeration industry. Table 1: Refrigerant/Lubricant Mixtures Studied 1. CFC-12/ISO 32 MO 13. HCFC-123/ISO 32 MO 25. HFC·152a/ISO 32 AB 2. CFC-12/ISO 100 MO 14. HCFC-123/ISO 100 MO 26. HFC-152a/ISO 68 AB 3. HCFC-22/ISO 32 MO 15. HCFC-123/ISO 32 AB 27. HFC-152a/ISO 22 POE-MA#1 16. HCFC-123/ISO 68 AB 28. HFC-152a/ISO 68 POE-MA#1 4. HFC-134a/ISO 68 PAG 5. HFC-134a/ISO 22 POE-MA#l 17. HFC-32/ISO 22 POE-MA#2 29. HFC•143a/ISO 22 POE-MA#2 6. HFC-134a/ISO 32 POE-MA#1 18. HFC-32/ISO 68 POE-MA#2 30. HFC-143a/ISO 68 POE-MA#2 7. HFC-134a/ISO 68 POE-MA#l 19. HFC-32/ISO 32 POE-BA 31. HFC-143a/ISO 32 POE-BA 8. HFC-134a/ISO 100 POE-MA 20. HFC-32/ISO 100 POE-BA 32. HFC-143a/ISO 100 POE-BA 9. HFC-134a/ISO 22 POE-BA 10. HFC-134a/ISO 32 POE-MA#2 21. HFC-125/ISO 22 POE-MA#l 33. HCFC-124/ISO 32 AB 11. HFC-134a/ISO 68 POE-BA 22. HFC-125/ISO 68 POE-MA#2 34. HCFC·124/ISO 68 AB 12. HFC-134a/ISO 100 POE-MA 23. HFC-125/ISO 32 POE-BA 24. HFC-125/ISO 100 POE-BA 35. HCFC-142b/ISO 32 AB MO=mineral oil, PAG=polyalkylene glycol, POE=polyolester ester, MA=mixedacid, BA=branchedacid, AB=alkylbenzene