Numerical Methods and Advances for Aeroacoustics

The relatively new field of computational aeroacoustics(CAA) has emerged in recent years. In this paper, the numerical methods, issues and development for aeroacoustics, were described, including finite difference scheme, boundary conditions and nonlinear acoustics and shocks. The characteristics of CAA and the difference between CAA and CFD-Computational Fluid Dynamics CFD were discussed. It is pointed out that the dispersion-relation-preserving finite difference schemes and appropriate nonreflecting boundary conditions are of critical importance to numerical methods for aeroacoustics. For the problem of nonlinear acoustics, the resolution of high-order differencing must be improved. In order to get exact numerical solution, some numerical procedure should be developed to eliminate oscillations with short wavelength, but the components of longer wavelengths are virtually unaffected.