Validation of a direct propagation model for liner impedance eduction

A Discontinuous Galerkin method used to solve the bidimensional harmonic Linearized Euler Equations is presented and tested, with the intention of building a new impedance eduction procedure in the presence of grazing ow based on Laser Doppler Anemometry measurements. Two di erent con gurations are considered for the numerical solver validation. The rst one is extracted from literature and involves Sound Pressure Level comparisons on the rigid wall opposite to the liner. The second benchmark concerns Laser Doppler Anemometry test results. Bidimensional velocity elds and projected velocity levels are studied. Despite small discrepancies, both cases generally reveal good agreement between numerical simulation and experiments. However important deviations arise at resonance frequencies, and no satisfactory explanation can be suggested at the moment. Finally, a quick re ection is initiated concerning the de nition of an adequate objective function for the inverse eduction problem.