An approach to developing a general technique for constructing reduced-order models of unsteady flows about three-dimensional complex geometries is presented. The boundary element method along with the potential flow is used to analyze unsteady flows over two-dimensional airfoils, three-dimensional wings, and wing-body configurations. Eigenanalysis of unsteady flows over a NACA 0012 airfoil, a three-dimensional wing with the NACA 0012 section and a wing-body configuration is performed in time domain based on the unsteady boundary element formulation. Reduced-order models are constructed with and without the static correction. The numerical results demonstrate the accuracy and efficiency of the present method in reduced-order modeling of unsteady flows over complex configurations.

Issue Section:
Additional Technical Papers
Keywords:
flow simulation, boundary-elements methods, aerodynamics, Laplace equations, aircraft
Topics:
Airfoils, Boundary element methods, Modeling, Unsteady flow, Wings, Eigenvalues, Wakes, Flow (Dynamics)
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 by ASME
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