Abstract: The Brinkman-Forchheime-extended Darcy model and the theory of equilibrium between fluid and porous medium were used to establish the mass conservation equation, momentum conservation equations and energy conservation equation of the two-dimensional laminar flow over an isothermal plate in porous medium. The equations were simplified by analyzing the order of magnitude of each item. The formulas of the velocity distribution and temperature distribution in the boundary layer, and surface viscous friction coefficient, convection heat transfer coefficient have been obtained by use of the integration method. It is shown that the boundary layer thickness in the porous medium increases very quickly at the beginning of the plate and reaches a steady thickness very soon, which is different obviously from that of a plain plate. But the thermal boundary layer thickness increases continuously along the flow direction and is similar to the situation of a plain plate.

Key words: Porous medium ,  Laminar forced flow over a plate , Boundary layer , Convection heat transfer ,  Integral solution

摘要： 对流体层流横掠多孔介质中等温平板的二维流动应用Brinkman-For chheime -ex te nded Da rcy 模型
和流体与多孔介质之间局部热平衡的传热理论建立质量方程、动量方程和能量方程, 应用数量级分析的方法对方程
组进行了简化, 并应用积分法得出了边界层内流体的速度分布、温度分布、以及摩擦系数和对流换热系数的理论表
达式。结果表明, 多孔介质中平板表面的速度边界层厚度与光板时有明显的不同, 其在平板前端迅速增长, 尔后变
得非常平坦并几乎不再增长;而热边界层厚度则和光板时类似, 沿着流动方向不断地增长。

关键词: 多孔介质 , 强迫层流横掠平板 , 边界层 , 对流换热 , 积分解