剪切液膜表面波的动力学特征和不稳定性  

Hydrodynamics and Instability of Shear Interfacial Waves of Liquid Films

作　　者：叶学民[1] 王松岭[1] 张营[1] 李春曦[1] 

机构地区：[1]华北电力大学能源与动力工程学院,河北省保定市071003

出　　处：《上海交通大学学报》2008年第8期1243-1246,1253,共5页Journal of Shanghai Jiaotong University

基　　金：高等学校博士点专项科研基金资助(20040079004)

摘　　要：通过求解沿倾斜壁面下降的液膜表面波的Orr-Sommerfeld方程,得到了长波波速表达式,结合剪切力作用下液膜的流动状态,分析了表面波扰动在初始时刻的不稳定性.研究表明:剪切液膜流动存在3种状态,由界面剪切力和重力纵向分量gsinθ决定;表面张力和重力横向分量gcosθ为稳定性因素,重力的纵向分量为不稳定性因素;剪切力对表面波的不稳定性作用与气流方向、剪切力大小和液膜的流动状态密切相关,在相同雷诺数和剪切力下,正向剪切力对液膜稳定性的影响更为显著.The wave velocity was presented based on the Orr-Sommerfeld equation for the liquid films draining down an inclined wall, and the instability at initial time was investigated with flow regimes under shear stress. The investigation shows that the sheared films have three regimes governing by interracial shear stress and gravity longitudinal component gsin θ. The surface tension and gravity longitudinal component are stable factors and the transverse component of gravity gcos θ is an unstable factor. The effect of shear stress is determined by the combination of flow regime and shear direction and its strength. Under the same Reynolds number and shear, the effect of cocurrent shear is more distinguished than that of coun- tercurrent shear.

关 键 词：液膜 表面波 剪切力 水动力学特性 不稳定性 

分 类 号：O352[理学—流体力学]