Magnetohydrodynamic non-Darcy mixed convection heat transfer from a vertical heated plate embedded in a porous medium with variable porosity
Magnetohydrodynamic non-Darcy mixed convection heat transfer from a vertical heated plate embedded in a porous medium with variable porosity
复制标题
嵌入可变孔隙率多孔介质中的垂直加热板的磁流体动力非达西混合对流换热
DOI：
10.1016/j.cnsns.2010.02.003
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发表时间：
2010
影响因子：
3.9
通讯作者：
D. Pal
中科院分区：
文献类型：
--
作者：
D. Pal
建立了考虑渗透率、孔隙度和导热系数变化的牛顿流体饱和稀疏填充多孔介质中垂直加热板混合对流的数值模型。多孔介质中的边界层流动由Forchheimer-Brinkman扩展达西模型控制。利用相似变换将控制问题的守恒方程简化为非线性常微分方程系统。由于非线性，控制方程采用数值求解。考虑多孔介质的均匀渗透率（UP）和变渗透率（VP），详细研究了磁场对速度和温度分布的影响，并对结果进行了图解讨论。此外，还计算了控制所考虑问题的各种物理参数的表面摩擦和努塞尔数。研究发现，在变渗透率情况下，惯性参数对增大流场和换热速率有显著影响。本工作的重要发现是磁场对多孔介质的边界层速度和变渗透率的换热率有相当大的影响。此外，在极限条件下得到的结果与已有的结果吻合较好。
A numerical model is developed to study magnetohydrodynamics (MHD) mixed convection from a heated vertical plate embedded in a Newtonian fluid saturated sparsely packed porous medium by considering the variation of permeability, porosity and thermal conductivity. The boundary layer flow in the porous medium is governed by Forchheimer–Brinkman extended Darcy model. The conservation equations that govern the problem are reduced to a system of non-linear ordinary differential equations by using similarity transformations. Because of non-linearity, the governing equations are solved numerically. The effects of magnetic field on velocity and temperature distributions are studied in detail by considering uniform permeability (UP) and variable permeability (VP) of the porous medium and the results are discussed graphically. Besides, skin friction and Nusselt number are also computed for various physical parameters governing the problem under consideration. It is found that the inertial parameter has a significant influence in increasing the flow field and the rate of heat transfer for variable permeability case. The important finding of the present work is that the magnetic field has considerable effects on the boundary layer velocity and on the rate of heat transfer for variable permeability of the porous medium. Further, the results obtained under the limiting conditions were found to be in good agreement with the existing ones.