The refrigerant vapor/liquid lubricant equilibrium viscosity reduction of two polyolesters (POE), viscosity grades 32 and 68 ISO VG, and one polyalkylene glycol (PAG), viscosity grade 68 ISO VG, were measured with R-507A from –5°C (23°F) to 125°C (257°F) up to 500 psia. All three lubricants have a miscibility curve starting at 2% and in increments up to 60% lubricant and refrigerant concentration determined from -40°C (-40°F) to 60°C (140°F). Using validated analytical methods, the viscosity, density, and composition of the solubilized gas mixture in solution with the lubricant are obtained. This refrigerant has a very small temperature glide, but it is still considered a blend.
Fractionation data were obtained from individual isothermal measurements. The isotherm for each temperature details the composition of the equilibrium of gas fractionation of R- 125 and R143a in the lubricant, mixed vapor pressure, concentration of the total mixed blend (percent by weight) in the lubricant, and viscosity in centipoises (cP) and centistokes (cSt).
Units: Dual
Citation: ASHRAE Transactions, vol. 111, pt. 1, Orlando 2005
Product Details
- Published:
- 2005
- Number of Pages:
- 10
- File Size:
- 1 file , 1.4 MB
- Product Code(s):
- D-25632
