Towards the development of adaptive finite element methods for internal flow aeroacoustics
We report the latest results obtained in the development of an adaptive finite element method for computational aeroacoustics (CAA). The new methodology is based on the General Galerkin (G2) method, which has been successfully used for the computation of incompressible, turbulent flow. Here, we simulate the flow past an in-duct mixer plate and compare the results with available experimental data. The comparisons include mean velocity profiles and frequency content of the turbulent signal. No direct simulation of sound or sound wave propagation has been performed; instead, simple analogy arguments have been used to extract acoustic results from incompressible simulations by assuming a direct correlation between the computed pressure drop signal and the sound at the far field. We were able to reproduce the sound signal from experiments with our incompressible simulation and our results compared well with both the level and the broadband frequency peak of the measured sound. We suggest that the methodology presented here is mainly suitable for the prediction of sound in low Mach number pipe flows.