Match-Point Solutions for Robust Flutter Analysis

The computation of robust e utter speeds presents a signie cant advancement over traditional types of e utter analysis. In particular, π-method analysis is able to generate robust e utter speeds that represent worst-case e ight conditions with respect to potential modeling errors. Robust e utter speeds may be computed using a model formulation that has been previously presented; however, that formulation has limitations in its ability to generate a match-point solution. A model formulation is introduced for which π-method analysis is guaranteed to compute a match-point solution. The match-point solution is immediately realized by analyzing a single model so the computation time is reduced from the previous approach that required iterations. Also, the solution is able to consider parametric uncertainty in any element, whereas the previous formulation did not consider mass uncertainty. The match-point formulation is derived by properly treating the nonlinear perturbations and uncertainties that affect theequation of motion. TheAerostructures Test Wing isused to demonstrate thatthe π-method analysis computes match-point e utter speeds using this new formulation.

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