FLOWFIELD ISSUES REL ATED TO TILTROTORS

ABSTRACT * This paper discusses results on several issues related to future tiltrotor craft. Experiments show that wing trailing edge flap deflection causes a lateral shift of the wake impingement region. Steady surface blowing to redirect the wake produces a 20 % improvement in the effect of the flaps, essentially eliminating download at a low forward speed. Flow visualization and large area velocimetry have been shown in large-scale experiments, efficiently enough to enable flow control experiments. Measurement distances have reached the values needed for measurements around full-scale vehicles. Instantaneous velocity field data suggest that cyclic pitch adjustments might enable a further reduction in download