Investigation on Miscibility of Lubricant and Mixed Refrigerant HFO-1234yf/HFO-1216

The HFO-1234yf/HFO-1216 mixture is a promising alternative refrigerant to HFC-134a due to its excellent environmental performance. Experimental investigation of the phase equilibrium between the mixture and lubricating oils is essential for screening suitable oils in practical refrigeration systems. In this work, an HFO-1234yf/HFO-1216 (80/20) composition was selected based on its overall performance and COP. The solubility of the mixture was measured in three linear pentaerythritol esters (PEC5, PEC7, and PEC9) over a temperature range of 283.15–343.15 K. The experimental data were correlated using the fugacity balance equation combined with the NRTL model. The calculated values show satisfactory agreement with the experimental data.