Actuation of an Active Gurney Flap for Rotorcraft Applications

Abstract

The goal of this research is to design and test configurations for an actively-deployed Gurney flap with applications to rotorcraft. Previous research has shown that Gurney flaps can offer significant performance gains when correctly deployed, but actuation methods remain to be developed. Gurney flaps require less power to actuate than a standard flap due to smaller hinge moments, which should result in light weight actuation systems. Highfrequency actuation methods have been investigated, and a concept employing a voice coil was developed. A mathematical model of this concept was developed to simulate dynamic performance and to ensure that the design could operate under the centrifugal (CF) loads experienced in a rotor blade. A prototype was built and preliminary bench testing was completed. This design met the required deflection and frequency requirements; however there were nonlinearities in the response that were not modeled. A new design involving the use of a piezoelectric bender augmented by CF loads is currently being developed and optimized. Preliminary results show that a CF-augmented bimorph may be a feasible actuation method for an active Gurney flap.