Different formulations for computational aeroacoustics
* Presenting author
Abstract:
Since the beginning of computational aeroacoustics, several numerical methodologies have been proposed, each of these trying to overcome the challenges that the specific problems under investigation pose for effective and accurate computation of the radiated sound. The difficulties which have to be considered for the simulation of flow noise problems include the energy disparity and acoustic inefficiency, length scale disparity, numerical dispersion, and dissipation to name just a few. In doing so, we will discuss the physics and challenges by its numerical computation of the following three methods. Firstly, Lighthill’s analogy, its extension by Curle as well as Ffowcs Williams and Hawkings are presented. Secondly, formulations based on a perturbation ansatz, e.g. acoustics perturbation equations (APE) or its reformulation of the perturbed convective wave equation (PCWE) are highlighted. Thirdly, direct numerical simulation solving the compressible flow equations and resolving both the transversal (vortical) and longitudinal (wave) structures are discussed.