Theoretical Analysis for Condensation Heat Transfer Performance Inside Converging-Shaped Microchannel Under Varying-Gravity Conditions

Abstract

Abstract The fast increasing heat-dissipation requirements under different working conditions such as varying gravity for aerospace industry is drawing more and more attention. Condensation inside microchannel is proved to be a promising technique to tackle this task. To comprehensively and accurately describe the physical phenomenon, a theoretical method considering both momentum exchange caused by vapor condensation and interface temperature drop is developed in this study. Reliability of our theoretical method is verified with both the Comprehensive Shah Correlation and established data. Condensation heat transfer inside converging-shaped microchannel is investigated and the influences of channel size, refrigerant mass flowrate, gravity variation, and converging angle are considered. Converging-shaped microchannel significantly enhances condensation heat transfer, especially for smaller channel with larger refrigerant mass flowrate. Influence of gravity change on condensation performances of vertically configured microchannels both with converging shape and constant cross-sectional area is small.