Characterization of Liners using a Lattice-Boltzmann Solver

Acoustic liners are widely used as noise suppression devices, for example in aircraft engines. The effectiveness of the liners is measured through the impedance. In the present study, using a lattice-Boltzmann solver, the response of two liner geometries to grazing acoustic waves is examined. The two geometries have porosity equal to 0.99% and 6.89%, respectively. Impedance is computed using the traditional in-situ method. The results from the simulation are validated against previous experimental data, DNS data and predictions from semi-empirical models. Results show agreement with these reference data, allowing to use the computational setup for further analysis with a realistic liner configuration in the presence of a grazing flow.