Analysis of Flapped Rotors Using CFD and Indicial Methods

A study of the potential performance enhancements via trailing-edge flap deployment has been conducted using a combination of CFD and indicial methods. Experimental data for validation of predictive methods for flapped rotors are rare, and this study was built around the HIMARCS I rotor for which some wind tunnel data are available in the open literature. Regarding hover performance, fixed flap configurations have been considered and it was found that some enhancement can be obtained. A parametric study has also been conducted to investigate the optimum flap location, size, and deflection angle. In forward flight, actuated flaps were implemented to alleviate the detrimental effects associated with dynamic stall. Several actuation schedules have been considered and results show the potential for improved rotorcraft performance at high speed forward flight by means of non-harmonic, flap actuation.