Interaction of a Synthetic Jet with Separated Flow over a Vertical Tail

Abstract

A coordinated experimental/computational study of synthetic jet-based flow control on a vertical tail/rudder assembly has been carried out on a 1/19th-scale model operating at 30 deg rudder deflection, 0 deg sideslip, and a Reynolds number of 350,000. Under these conditions, a very strong spanwise separated flow develops over the rudder surface for a majority of its span. Twelve synthetic jets were distributed across the span of the vertical tail just upstream of the rudder hinge line to determine their ability to reduce flow separation, thereby increasing the side-force production and rudder effectiveness. The current study provides a detailed comparison between the experiments and delayed detached-eddy simulation computations for the baseline flow and the case where one jet is active. Specifically, the origin of the strong spanwise flow close to the rudder surface is detailed for the baseline case. For the one jet active case, the positive effects of the jet on the separated flow are described through a complex phenomenon that resembles the root separation. Finally, the capacity of the delayed detached-eddy simulation turbulence model to capture the physics of the baseline and forced cases and predict the resulting side force is validated with respect to corresponding experiments.