Sunroof Buffeting of a Simplified Car Model: Simulations of the Acoustic and Flow-induced Responses

Sunroof buffeting of a simplified car model was investigated experimentally and numerically in order to assess the potential of numerical methods to design sunroofs that are quiet and functional. The numerical results have been obtained using the commercially available software PowerFLOW. The simulation kernel of this software is based on the numerical scheme known as the Lattice Boltzmann Method (LBM), combined with an RNG turbulence model. This scheme accurately captures time-dependent aerodynamic behavior of high Reynolds number flows over complex geometries, together with the acoustic response of resonant systems.

In this work, a simplified car model with a sunroof was used for validation. A simulation methodology to determine the acoustic response of the passenger cabin was investigated and verified experimentally. The sunroof buffeting phenomenon was simulated over a range of flow conditions, and the results were found to be in good agreement with experimental data. Small discrepancies in the buffeting onset and offset velocities were observed, attributed to small geometric and flow differences between physical and simulated domains.