HFO1234ze(E) vaporisation inside a Brazed Plate Heat Exchanger (BPHE): Comparison with HFC134a and HFO1234yf

This paper investigates the effects of heat flux, saturation temperature, and outlet conditions on HFO1234ze(E) boiling inside a Brazed Plate Heat Exchanger (BPHE). The effect of the heat flux on the heat transfer coefficients was remarkable. Similar consideration applies for outlet condition effects whereas the impact of saturation temperature was found to be lower. The frictional pressure drop shows a linear dependence on the refrigerant kinetic energy per unit volume. The two-phase flow boiling heat transfer coefficients were compared with a new model for refrigerant boiling inside BPHE (Longo et al., 2015): the mean absolute percentage deviation between calculated and experimental data is 7.2%. The present data points were compared with those of HFC134a and HFO1234yf previously measured inside the same BPHE under the same operating conditions: HFO1234ze(E) exhibits heat transfer coefficients very similar to HFC134a and HFO1234yf and frictional pressure drops slightly higher than HFC134a and HFO1234yf.