热边界层相似性解条件及其相似性解方程

边界层是相似的,其含义就是对不同断面的速度或焓分布,都可以通过调整坐标的尺度因子,使它们重合在一起。一般说来,寻求相似性变量以及把相应的边界层偏微分方程转化为常微分方程的方法均不是唯一的。本文拟对层流流动边界层和热边界层叙述一种通用性较好又比较简洁的方法。

Existent Conditions of Similar Solutions and its Equations for Thermal Boundary Layers

We shall define here "similar" solutions as those for which the velocity and the temperature profiles at all different values of x can be made congruent if they are plo- tted in coordinates that have been made dimensionless with reference to the suitable scale factors. Obviously, when similar solutions exist, it is quite possible for the System of partial differential equations to reduce to ordinary differential equations, which, evidently, constitute a considerable mathematical simplification of the problem. The quest for similar solutions, therefore, is of paramount importance. Finally, the existent conditions of similar solutions are investigated and the methods to transform the partial differential, equations of boundary layer to an odinary differential equations of similar solutions are proposed.