Uncertainty and Reliability Analysis of Fluid–Structure Stability Boundaries

Fluid–structure interactions provide design constraints in many fields, yet methods available for their analysis normally assume that the structural properties are exactly known. In this contribution, these properties are more realistically modeled using random fields. Stochastic finite element methods are applied to perform uncertainty and reliability analysis on fluid–structure interaction problems with random input parameters. As an example we consider panel divergence and panel flutter. Numerical simulations demonstrate the appropriateness of sensitivity-basedmethods for characterization of the statistical moments of the critical points as well as for the determination of the probability of occurrence of undesired phenomena. Nomenclature a = discrete solution vector a1 = freestream fluid speed of sound C = damping matrix of the coupled system Cy = confidence level of sampled variable y C?y = confidence level of y with discretization error E = modulus of elasticity f = right-hand side vector h = panel length K = stiffness matrix of the coupled system lc = characteristic length of the random field M = mass matrix of the coupled system m = number of random variables used for random field parametrizatio