多孔介质中非线性延伸壁面上驻点流动的非相似解

Non-similarity solutions of stagnation-point flow over a nonlinear stretching sheet embedded in a porous medium

基于不可压缩粘性流体在多孔介质中的流动,考虑孔隙率和渗透率的影响,研究多孔介质中非线性运动延伸壁面上的驻点边界层流动问题.引入无量纲变换将边界层控制方程化简,通过同伦分析方法求得方程的非相似解.再利用同伦解讨论多孔介质孔隙率、渗透率以及非线性参数等重要参数对流体速度分布和表面摩擦力的影响.结果显示:多孔介质中孔隙率参数和非线性参数对达西速度剖面的影响作用大于渗透参数的影响.

The stagnation-point flow towards a nonlinear stretching sheet based on incompressible viscous flow had been mainly investigated,considering the effects of the porosity and permeability of a porous medium. Introducing the dimensionless transformations,the governing equations describing the stagnation point flow were reduced and solved by homotopy analysis method,which was introduced to obtain the non-similarity solutions of the governing equations. The influences of the important parameters including porosity,permeability and nonlinear parameter on the skin friction coefficient and velocity profile were discussed in detail. The results showed that the impact of porosity and nonlinear parameter were larger than the permeability on velocity profile.