High-precision acoustic simulation of a turbulent flow over a curved body

A. V. Aleksandrov^a, L. V. Dorodnitsyn<sup>b

a</sup> Keldysh Institute of Applied Mathematics, Russian Academy of Sciences, Moscow, Russian Federation
^b Lomonosov Moscow State University, Moscow, Russian Federation

Abstract: We present a method for numerical modeling of acoustic disturbances generated by the scattering of artificially created turbulent fields on curved obstacles. We performed the calculations using dispersion-preserving finite-difference schemes commonly applied in computational aeroacoustics. These schemes employ wide stencils, providing high accuracy and resolving high-frequency harmonics. Given the wide stencil, we focused on the problem of setting numerical boundary conditions on the surface of a solid body. We applied an approach using a ghost point located inside the solid body near the boundary, outside the computational domain. We obtained new theoretical results for curved boundaries. To generate the artificial turbulent field, we applied a previously developed method of tensor filtering of white noise, adapted to a two-dimensional formulation. We present results of modeling the scattering of a turbulent wake on an elliptical cylinder, demonstrating the formation of pressure waves using this approach.

Keywords: acoustics, synthetic turbulence, difference schemes, dispersion-relation-preserving scheme.