The effect of an intake vortex on the frontal boundary layer

The three-dimensional boundary layer at the intake of a blade cascade is investigated experimentally using a needle probe. It is shown that an intake vortex does not cause the boundary layer to separate but affects the local characteristics of the latter. Thus, extreme values of the integral characteristics of the boundary values are recorded in the wake of a vortex, the effect of the vortex on the longitudinal velocity component being particularly strong. The effect of the vortex is shown to depend on flow conditions in the flow core and is less pronounced in reactive cascades.