微结构壁面降膜波动的统计特性

Statistical Characteristics of Wavy Falling Films over Micro Textured Surfaces

摘要: 采用非接触测量法，考察了以水为实验体系，中等雷诺数Re为30~200，卡比萨数Ka=6.23×1010，刻有竖条纹和菱形条纹微结构壁面上液膜的波动统计特性，如平均液膜厚度、标准方差、波动振幅量纲一液膜衬底厚度、波动频率等，并与光滑不锈钢板上液膜特性进行比较，结果表明：即使在微结构壁面，液膜波动同样存在光滑进口区，微结构壁面上液膜的平均液膜厚度、波动振幅和波动频率均大于光滑不锈钢板，微结构壁面和光滑不锈钢板上液膜波动性的演变趋势沿流动方向及随Re变化均基本一致。

Abstract: The statistical characteristics of falling films over surfaces with two different textures of vertical and diamondshaped grooves on aluminum plate were studied at intermediate Reynolds numbers (30