SUBCRITICAL FLUTTER CHARACTERISTICS OF A SWEPT-BACK WING IN A SUPERSONIC-FLOW

The purpose of this paper is to investigate subcritical flutter charac teristics of a cantilever swept-back wing in a turbulent supersonic fl ow using computer simulation. This is a counter-part analysis for the nonstationary experiment made by one of the authors in a previous stud y. Comparison between the analysis and the experiment shows that the v ariance of Jury's stability parameter estimated from a very short time record decreases monotonically toward zero as the dynamic pressure ap proaches the Butter boundary, whereas the variance of the damping esti mated with the same condition remains large. The flutter boundary is p redictable by the intersection of the upper straight line of an envelo pe enclosing the scattered values of Jury's stability parameter F- (3) with the horizontal coordinate. The flutter prediction based on Jury' s stability parameters is more effective in practical application than the conventional damping method.