Using solubility data for HFC-134a and ester lubricant mixtures to model an in-tube evaporator or condenser
- Additional Document Info
- View All
Refrigeration systems typically have small amounts of lubricant circulating through the evaporator and condenser. However, in the high-quality region of a heat exchanger, the amount of lubricant present in the liquid phase can be significant, thus changing the saturation temperature of the refrigerant/lubricant mixture. In this study, solubility data are used to explain temperature measurements obtained for a refrigerant/lubricant mixture at the inlet and exit of an evaporator and condenser. The significance of these solubility effects on determining two-phase heat transfer coefficients for refrigerant/lubricant mixtures is also discussed. As part of this study, solubility data are presented for HFC-134a and a 169 SUS and 369 SUS penta erythritol ester mixed acid over a temperature range of -10 °C (14 °F) to 50 °C (122.0 °F) for lubricant concentrations from 0% to 45%. The data were statistically correlated and solubility equations are presented. The range of temperatures and concentrations evaluated reflects conditions typically found in a refrigeration-type evaporator or condenser.
author list (cited authors)
Eckels, S. J., Zoz, S. C., & Pate, M. B.