Suction and Pulsed Blowing Applied to Local Separation Downstream of Slat Cutout

Abstract

An experimental study on the application of active flow control (AFC) to a .4 scale model of a swept wing in a landing configuration was conducted. The wing is fitted with an ultrahigh bypass ratio (UHBR) engine nacelle. The highly efficient UHBR engines are characterized by a large diameter that interferes with the flow around the wing, especially with slats deflected, degrading its performance. An innovative AFC device, creating steady suction and pulsed blowing (PB), was installed in the leading-edge region of the wing, above the nacelle, and its performance was experimentally evaluated. The effects of the suction and PB mechanisms were examined individually and simultaneously using relevant normalized parameters to pave the way to a full-scale wind-tunnel test. It was shown that the AFC actuators increased lift by up to 3%, redirected the flow to the desired downstream direction, and reduced the size of the separation zone created due to the implementation of the UHBR nacelle. The next step is validating the small-scale results of this study in a full-scale wind-tunnel tests that would be the last step before the technology is flight test ready.