MOVING WALL EFFECT IN RELATION TO OTHER DYNAMIC STALL FLOW MECHANISMS

An analysis is performed to determine the importance of the so-called moving wall effect relative to other unsteady now mechanisms present in the dynamic stall process. Analysis of existing theoretical and experimental results indicates that the tangential moving wall effect on the initial boundary-layer development, close to the flow stagnation point, is not satisfactorily represented in current numerical methods. The analysis shows that this moving wall effect plays a dominant role in inducing self-excited oscillations, such as the wing rock of advanced aircraft, and also plays a significant role in so-called supermaneuvers of these aircraft.