18 May 2017

O.4.1.4 Research on condensation heat transfer characteristics of R447A, R1234ze, R134a and R32 in multi-port micro-channel tubes


The condensation heat transfer characteristics of R447A (R32/R1234ze/R125) in multi-port extruded micro-tubes (MPE) with inner diameter of 0.86 mm were investigated by experimental and compared the results of R134a, R32 and R1234ze.The experiments were conducted under the mass fluxes ranged from 100 to 400 kg/m2.s,and saturated temperatures from 35 to 45 oC. The results show that the heat transfer coefficient of R447A was lower than that of R32 greatly and R134a slightly, but higher than R1234ze. On the basis of six revised correlations, the predicted mean absolute errors were within 30% compared with the experimental values.