Simplified analysis of sectional airloads on morphing airfoils

In recent years, interest has increased in employing dynamically morphing airfoils for rotorcraft. Morphing airfoils have been studied and shown effective in increasing lift, reducing vibration, and alleviating dynamic stall. With improvements in individual blade control and actuation technologies, the practical application of morphing airfoils is becoming increasingly possible. One difficulty that morphing airfoils introduce for aerodynamic analysis is the need to obtain static airfoil lift, drag, and pitching moment data for any arbitrary airfoil shape. This paper outlines a method for parameterizing airfoil data in terms of generalized airfoil velocities, resulting in static characteristics for any arbitrary shape based on a small number of static tests. This process is demonstrated by correlating CFD data for the SC-1095 airfoil, which is representative of modern helicopter rotor airfoils. Furthermore, the the static data are used to predict dynamic-stall airloads with a unified airloads model.