Direct numerical simulation of aerodynamic sounds by a compressible CFD scheme with node-by-node finite elements

A direct numerical simulation (DNS) of aerodynamic sounds is performed by using a compressible CFD scheme with node-by-node finite elements. Although the computational simulations of aerodynamic sounds generated from three-dimensional objects with complex boundary shapes are required in various industrial applications, such simulations involve a lot of difficulties regarding instability in numerical schemes and enormous computational costs. In this paper, the present authors have combined the C-CUP (CIP-Combined Unified Procedure, CIP: Constrained Interpolation Profile) method and the CIVA (Cubic Interpolation with Volume/Area Coordinates) method with the Free Mesh Method (FMM) in order to achieve efficient simulation of aerodynamic sounds using unstructured computational grids of finite elements on parallel computers. As a numerical example, the edge tone is successfully computed using the present method with parallel computing with Hitachi SR8000 supercomputer.

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