多孔表面微细结构内的蒸发换热

Evaporation heat transfer inside the micro-structure of porous surfaces

为了研究多孔槽道几何参数对多孔表面沸腾换热性能的影响 ,从分析多孔结构内微液膜蒸发和气液两相流的机理出发 ,借鉴微热管的研究方法 ,建立了描述多孔表面沸腾换热的细观动态模型。通过对沸腾起泡点分布的简化处理 ,进行了数值求解 ,计算结果与已有文献的实验数据一致。计算结果还表明 :对于微液膜换热 ,存在最佳液膜厚度 ,使液膜换热热阻最小。利用该模型 ,导出了多孔表面在常用沸腾工质中沸腾换热时的结构优化参数。

The geometric parameters of micro structures greatly influence the boiling heat transfer performance of porous surfaces. Analysis of the micro film evaporation and the two phase flow inside the porous micro structure was used to develops using the Micro Heat Pipe (MHP) research method. The simulation results, which fit previous experimental data well, showed that an optimum film thickness exists which gives the least thermal resistance in the micro film heat transfer process. The model was used to determine the optimum micro structure dimensions for boiling on porous surfaces for some common working fluids.