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研究了液膜流动破裂的基础机理,构建了考虑表面张力、重力、惯性力及剪切应力等因素的液膜动力模型,采用边界层积分法,引入含有三次项剪切力项的速度分布函数,推导二维稳态水平管外环向液膜的厚度方程.通过数值方法求解该厚度方程,得到水平管外环向液膜厚度的分布规律.结果表明,随环向角度增大,环向液膜厚度先减小后增大,最薄液膜位置角在环向90?之后,且流量、剪切应力系数与管径等因素不改变环向液膜厚度的分布趋势,改变了环向最薄液膜位置角.最薄液膜位置角随流量增大、剪切应力系数减小及管径减小而增大.表面张力是影响环向液膜稳定性不可忽略的因素.
The basic mechanism of liquid film rupture was studied, and the dynamic model of liquid film considering the factors of surface tension, gravity, inertial force and shear stress was constructed. The boundary layer integral method was introduced to introduce the velocity distribution function , The thickness equation of the liquid film in the two-dimensional steady-state horizontal tube is deduced. By solving the thickness equation numerically, the distribution rule of the thickness of the liquid film in the horizontal tube is obtained. The results show that with the increasing of the annular angle, The thickness of the liquid film first decreases and then increases, the position of the thinnest liquid film after the 90 ° ring direction, and the factors such as the flow rate, the shear stress coefficient and the diameter of the liquid film do not change the distribution trend of the circumferential liquid film thickness, The position of the thinnest liquid film.The position angle of the thinnest liquid film increases with the increase of flow rate, the decrease of the shear stress coefficient and the decrease of the diameter of the liquid film.The surface tension is a factor that can not be ignored in the stability of the liquid film in the circumferential direction.