Heat pump, Cycle simulation, HFO, R1234ze(E), R32, Heat transfer
A low GWP refrigerant R1234ze(E) is focused as a candidate of next-generation refrigerant though it has some defects which are low operating pressure and low latent heat. Mixing R32 into R1234ze(E) expects to reduce the defects because R32 has high operating pressure, large latent heat and high thermal conductivity. In order to prove the possibility, heat transfer coefficients during condensation and evaporation were obtained experimentally and cycle simulations were carried out where heat transfer degradation of refrigerant mixture was estimated with the experimental data. An equivalent performance with conventional refrigerant was obtained by the simulation.