Abstract
A new technique for the numerical analysis of aerodynamic noise generation is developed. The approach involves first solving for the time-dependent incompressible flow for the given geometry. A “hydrodynamic” density correction to the constant incompressible density is then calculated from knowledge of the incompressible pressure fluctuations. The compressible flow solution is finally obtained by considering perturbations about the “corrected” incompressible flow. This fully nonlinear technique, which is tailored to extract the relevant acoustic fluctuations, appears to be an efficient approach to the numerical analysis of aerodynamic noise generation, particularly in viscous flows. Applications of this technique to some classical acoustic problems of interest, including some with moderately high subsonic Mach numbers, are presented to validate the approach. The technique is then applied to a fully viscous problem where sound is generated by the flow dynamics.
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Communicated by M.Y. Hussaini
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Hardin, J.C., Pope, D.S. An acoustic/viscous splitting technique for computational aeroacoustics. Theoret. Comput. Fluid Dynamics 6, 323–340 (1994). https://doi.org/10.1007/BF00311844
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DOI: https://doi.org/10.1007/BF00311844