An Automated Method for Determining the Flutter Velocity and the Matched Point

A new method is developed for the automated determination of flutter solutions and the matchedpoint flutter density. The method employs a Laguerre iteration technique and closed-form analytical expressions to compute the first and second derivatives of damping with respect to inverse of reduced frequency and of flutter velocity with respect to square root of inverse of air density. The mathematical development of the method is discussed, and the results of applications of the method to an all-movable control surface and transport-type wing are presented. The efficiency and accuracy are compared to the traditional damping-velocity graphical method. The results indicate that the new technique is accurate and fast and is well suited for use in automated flutter design. The use of the method in aeroelastic optimization and potential application to thep-fe method are discussed.