Abstract This work investigated the effect of liquid film thickness and surface roughness ratio on the rapid boiling of water over the copper plates in terms of hydraulic diameter defined based on the overall cross-sectional area available for the flow of water film. It is found that the reduction of the hydraulic diameter by increasing the surface roughness ratio can substantially promote the performance of rapid boiling, because of the increase in heat transfer area, together with a decrease in the Kapitza resistance. As a combined effect of the film thickness and the Wenzel roughness ratio, the hydraulic diameter can determine the onset time of boiling and the equilibrium temperature, while it can also determine the heat transfer rate and the Kapitza resistance if the film thickness or the surface roughness is fixed. The effects of the hydraulic diameter on the performances of nanoscale boiling can be applied for heat transfer enhancement and process intensification over any structure in phase-change devices and chemical equipments.

中文翻译：

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液膜厚度和表面粗糙度比对铜板上水快速沸腾的影响

摘要 这项工作根据基于可用于水膜流动的总横截面积定义的水力直径，研究了液膜厚度和表面粗糙度比对铜板上水快速沸腾的影响。发现通过增加表面粗糙度比来减小水力直径可以显着提高快速沸腾的性能，因为传热面积增加，同时卡皮察阻力降低。作为膜厚和温泽尔粗糙度比的综合作用，水力直径可以决定沸腾开始时间和平衡温度，而如果膜厚或表面粗糙度，它也可以决定传热速率和卡皮察阻力。是固定的。