Cymbal type Piezo-Polymer-Composite actuators for active cancellation of flow instabilities on airfoils

This paper presents the design and fabrication of a Cymbal type piezo actuator in Piezo-Polymer-Composite (PPC) technology. The purpose of the developed actuators is, in combination with a full setup including flow sensors, a digital control system, and an elastic membrane, an active manipulation of boundary layer disturbances at airfoils. The goal is to reduce the friction drag on an airfoil by delaying the transition from a laminar to a turbulent boundary layer. The presented results of wind tunnel experiments will prove the successful accomplishment of this task. Boundary layer instabilities, the cause for the transition, are dampened by more than 80%.