HEAT TRANSFER AND PRESSURE DROP DURING CONDENSATION OF R-134A INSIDE PARALLEL MICROCHANNELS

摘要

In this study the pressure drop and local heat transfer coefficient were investigated experimentally during the convective condensation of R-134a inside eight round (D= 0.8 mm) horizontal and parallel microchannels. The test conditions included mass velocity and pressure ranges of 57 to 125 kg.m~(-2) s~(-1) and 6.8 to 11.2 bar, respectively. The experimental results are compared with correlations and semi-empirical models described in the literature.