A Fundamental Study of Wake-Boundary Layer Interaction on Turbomachinery Blading

Turbulent boundary layers on turbomachine blades are three-dimensional and highly unsteady. The flow becomes periodically unsteady due to the relative motion of the rotor and stator blades in a stage. A large velocity defect within the wake of an upstream blade generates a varying incidence angle, and a fluctuating velocity at entrance to the next stage. The velocity defect, or wake, travels downstream with a finite speed and intermittently perturbs the boundary layer on downstream blades.