Applications of a High-Frequency Aerodynamic Theory to the Calculation of Flutter at Supersonic Speeds

摘要

Flutter of airfoil sections in bending, torsion, and control-surface rotation at supersonic flight speeds is analysed by employing an aerodynamic solution for highfrequency oscillations. The analysis includes effects of airfoil thickness and shape, and is valid at arbitrary supersonic Mach numbers and sufficiently high values of frequency variable. For flutter problems with two degrees of freedom (bending-torsion, bending-aileron, torsionaileron) explicit expressions for calculating the flutter speed and frequency are obtained. The case of three degrees of freedom (bending-torsion-aileron flutter) is studied by solving the determinant equation numerically. Some calculated results are presented, showing the variation of flutter boundaries with the elastic and inertial properties of the airfoil, the flight conditions and the airfoil thickness. (Author)