High resolution central schemes for multi-dimensional non-linear acoustic simulation of silencers in internal combustion engines

Because of their small numerical viscosity even when very small time steps are enforced, central schemes look very suitable for acoustic simulations of silencers in internal combustion engines. In this work, a high resolution central scheme has been used with ad-hoc developed boundary conditions for the generation of different acoustic perturbations (white noise, sweep, impulse) in the OpenFOAM® technology. The temporal solution, carried out by a first-order integration of the conservation laws by the explicit Euler’s method, has been first transferred into the frequency domain using FFT and then it has been processed to evaluate the transfer function of different geometries of silencers for internal combustion engines. The results obtained from the simulations have been compared with experimental data.