Dynamic interaction between boundary layer flow and groundwater flow separated by a porous bed

Abstract

This paper examines the problem of dynamic interaction between a steady-state axisymmetric boundary layer flow over a fluid-saturated porous bed and a uniform Darcy flow occurring in the bed. The analysis is based on the selection of an appropriate boundary condition to account for the existence of tangential slip at the permeable interface separating the two flows. Numerical solutions are presented for different values of permeability parameter K and the characteristic Reynold number Re of the potential flow impinging on the porous bed. It is shown that when K 2 Re < 1 , there exists a thin sublayer attached to the bed in which the normal velocity of the fluid is directed upwards. Response of pressure distribution in the boundary layer and shear stress on the bed to variations in K and Re has also been examined.