Time dependent RANS computations for an aeroelastic wing

A computational procedure for performing fluid-structure interaction computations for three-dimensional wing geometries is developed here. The flow solver is modeled using an unsteady Reynolds-Averaged Navier-Stokes (RANS) model. We use a predictor-corrector-based PISO (Pressure Implicit Splitting of Operators) algorithm to perform unsteady flow computations. The choice of this approach greatly reduces the computational cost for CFD computations as compared to the iterative scheme employed before. The structure is modeled using Bernoulli-Euler beam theory. Modal analysis is used to solve the equations of motion of the structure. An appropriate moving boundary technique based on master & slave concept and transfinite interpolation method is adopted to remesh the entire flow domain after each time step. Accurate computation of contravariant velocities for unsteady flows using momentum interpolation method on collocated, curvilinear grids is addressed in this paper. Generalized displacements from the coupled fluid-structure interaction computation for first two bending modes of the structure are shown using the AGARD 445.6 wing geometry.