Mixed Convection Boundary Layer Flow Near the Stagnation Point on a Vertical Surface With Slip
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摘要: 就粘性不可压缩流体,研究垂直壁面的滑移,对壁面驻点附近稳定混合对流边界层流动的影响.假定表面温度和外部流动速度与到驻点的距离呈线性变化.首先,将偏微分的控制方程,转变为常微分方程组,然后应用打靶法进行数值求解.对不同数值的控制参数,按分顺流和逆流两种情况,分析和讨论了流动特性和热传导特征.结果表明,逆流时,在浮力参数的某一范围内出现双解;顺流时,解是唯一的.一般而言,速度滑移导致壁面热传导率增大,而热滑移使之减小.Abstract: A steady mixed convection boundary layer flow of a viscous and incompressible fluid near the stagnation point on a vertical surface with slip effect at the boundary was considered. The temperature of the sheet and the velocity of the external flow were assumed to vary linearly with the distance from the stagnation point. The governing partial differential equations were first transformed into a system of ordinary differential equations, which was then solved numerically by a shooting method. The features of the flow and heat transfer characteristics for different values of the governing parameters were analyzed and discussed. Both assisting and opposing flows were considered. The results indicate that for the opposing flow, dual solutions exist for a certain range of the buoyancy parameter, while for the assisting flow, the solution is unique. In general, the velocity slip increases the heat transfer rate at the surface, while the thermal slip decreases it.
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Key words:
- dual solutions /
- heat transfer /
- mixed convection /
- stagnation point /
- slip
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