关键词:

冷凝, 传热, 微通道, 毛细力

Abstract: Condensation in microchannels has been widely used in a variety of advanced micro thermal devices, such as micro heat pipe and micro fuel cell.Presented here is a review of investigations of condensation in microchannels.The future progress is also presented.Extensive research indicates that surface tension, rather than body or buoyancy forces, is the dominant force that governs the condensation and two-phase flow in microchannels.Recent experimental results show that with the decrease in channel diameter, the dominant condensing flow pattern is intermittent injection/slug/bubble flow, as opposed to stratified annular flow, which are typically found in larger one-g channel flows.As a result, existing condensation models without considering surface tension can not be used to accurately represent or predict the actual physical mechanisms that occur in these condensing flows in microchannels.This, therefore necessitates the use of semi-theoretical models or correlations based upon experimental data.Since wettability and surface roughness play an important role in the condensing flow in microchannels, an optimization of these effects may provide a mechanism by which very high condensation heat fluxes can be achieved.

Key words:

冷凝, 传热, 微通道, 毛细力