Blade response simulations of flap controlled stopped rotors

Abstract

A simplified trim procedure coupled with the nonlinear P.D.E. solver is developed to simulate elastic blade tip deflections during rotor stopping transition. A conditionally stable explicit finite difference scheme is used to numerically integrate the nonlinear partial differential equations of motion in space and time to obtain the aeroelastic transient response of a hingeless rotor blade with trailing edge flap controls. New aerodynamic environment due to flap control is formulated based on Theodorsen's unsteady oscillating airfoil aerodynamics representation including unsteady trailing edge flap motions.