The laminar boundary layer with injection through a permeable wall

The steady incompressible laminar boundary layer equations for a perfect gas with arbitrary distributions of wall temperature, main stream velocity and normal velocity at the wall are solved approximately by a method similar to that of Lighthill (1950). Equations for the skin friction and the rate of heat transfer are obtained. In order to assess the accuracy of these equations, solutions are presented and compared with exact solutions for wedge type flow with a wall temperature distribution such that the difference between the wall and the stream temperatures is proportional to a power of the distance from the leading edge. A Prandtl number of 0 7 is used. A solution for the skin friction with a constant normal velocity at the wall and constant main stream velocity is also presented. The method is probably accurate enough for engineering purposes in regions of negative pressure gradient. A solution for compressible flow using a similar method is outlined.