The aerodynamic sound produced by a wing in unsteady flow is computed numerically. A boundary element method is used to calculate both the aerodynamic flow and the sound radiated in an attempt to provide a unified and computationally efficient method. This method is intended to help fill the gap between numerically expensive techniques (e.g., RANS, LES) and analytical methods which are available only for a small subset of the wing geometries of interest.; The advances made in the current research are through the incorporation of several previously developed techniques in boundary element and vortex methods and their aggregate application to the present aerodynamic sound problem. The method is capable of modeling general three-dimensional wing geometries with a multiple number of wing elements (e.g., flaps) and with thin shear layer wakes that evolve freely with the unsteady flow. The passage of a vortex filament, which also evolves freely and nonlinearly, can be simulated to study the Blade-Vortex Interaction (BVI) problem. Validations with two-dimensional analytical solutions for parallel BVI show that the lift spectra are computed to within 1 dB up to nondimensional frequencies (scaled by the freestream velocity and the half-chord length) of about 10 using only 40 panels along a streamwise wing section.; The parallel BVI problem was used to investigate the effects of wing geometry. These results show that the high frequency response is significantly reduced for high thickness, camber, sweep, and taper, but is increased for high angle of attack and flap deflection angle. The most important parameters affecting the BVI signal is observed to be the minimum separation distance between the vortex filament and the wing. It is shown that the correct separation distance is only achieved when the vortex is modeled as evolving freely and nonlinearly.
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