基于COMSOL PDE仿真的垂直板驻点混合对流与传热

Mixed convection stagnation-point flow towards a stretching vertical sheet based on COMSOL

研究了不可压缩粘性流体在垂直指数延伸壁面上的边界层流动与传热问题．通过相似变换将边界层控制方程转换为非线性常微分方程，并利用COMSOL软件的PDE（偏微分方程）模块进行仿真求解．讨论顺流和逆流时浮力参数λ和Prandtl数Pr对流体流动和传热特性的影响．结果显示：顺流时，表面摩擦系数和Nusselt数均随浮力参数λ的增大而增大；随着Pr数增大，Nusselt数增大而表面摩擦系数减小．逆流时，表面摩擦系数和Nusselt数均随浮力参数λ的增大而减小，随Pr增大而增大．

The paper studies the mixed convection flow and heat transfer of an incompressible viscous fluid about a stagnation-point on an exponentially vertical stretching sheet. The governing equations describing the stagnation-point flow are reduced to a differential equation by using the similarity transformations. Then employing PDE module in COMSOL software to solve the nonlinear problem. Finally, the effects of the buoyancy parameter and the Prandtl number parameter on the features of the flow and heat transfer characteristics are analyzed and discussed in detail. The results show that for assisting flow, both the skin friction coefficient and the Nusselt number increase as the buoyancy parameter increases; but only the Nusselt number increases the skin friction coefficient decreases as the Prandtl number increases. For opposing flow, both the skin friction coefficient and the Nusselt number decrease as the buoyancy parameter increases, while both increase as Pr increases.