An Active Flap Deployment System for Blade–Disturbance Interaction Alleviation

Abstract

A new, actively deployable trailing edge flap system is introduced and an experimental investigation is undertaken to determine its effects on the disturbances created during blade–disturbance interactions (BDI), with blade–vortex interaction (BVI) alleviation being the ultimate objective. Experimental tests were conducted using a two-dimensional (2D) wind tunnel setup incorporating a pressure instrumented airfoil section with a deployable 20% trailing edge flap and an upstream vortex generator to produce the disturbance. Results of this study showed that the disturbances, caused by BDI events, to the pressure distribution over the airfoil occur mostly at the leading edge. Carefully synchronized deployment of the trailing edge flap during BDI events resulted in a reduction of this pressure disturbance. The aeroelastic response of the active flap was modeled via unsteady linear theory and the model was validated experimentally. The aeroelastic model shows good agreement with experimental results, which supports its use as a preliminary design tool for the actuation parameters of the active flap system.