Theoretical and experimental assessment of propane and propylene as substitutes for traditional HFC refrigerants R410A and R404A

This paper presents the heat-transfer assessment of propane and propylene as low-GWP substitutes for traditional HFC refrigerants R410A and R404A by applying both an experimental analysis based on the direct measurement of thermal and hydraulic performances and a theoretical analysis based on a specific Performance Evaluation Criteria (PEC), the Total Temperature Penalisation (TTP), in the specific case of boiling and condensation in a commercial Brazed Plate Heat Exchanger (BPHE). The results of both the experimental and the theoretical assessment show that propane and propylene exhibit boiling heat transfer characteristics comparable to R404A and lower than R410A, while in condensation propane and propylene perform like R410A and better than R404A. Propylene performs slightly better than propane both in boiling and condensation. The coupling of experimental and theoretical assessments provides a sound procedure for the heat-transfer assessment of the low-GWP alternatives for traditional HFC refrigerants.