Axial flow past a cylinder with uniform injection

An analytical investigation of the injection of fluid into the axial flow past a cylinder is presented. The boundary-layer equations of the flow are derived and solved by a similarity approximation for cases in which m (the injection Reynolds number referred to cylinder radius) = 1 and for those with m much greater than 1. The solutions are shown to be valid at sufficiently large axial distances from the cylinder nose. The wall shear stress is found to be greatly reduced by injection at m = 1, whereas for m much greater than 1 the flow splits into a thick region of radial flow and a thin axially symmetrical shear layer with a shear stress at the cylinder of about zero. The possible implications of these calculations for heat-exchange reduction during spacecraft reentry are indicated.