Numerical study of an in-situ technique for measuring surface impedance and reflection coefficient with p-u probes
The characterization of the acoustic sound pressure and velocity field on the surface of absorbing materials plays a key role for the computation of their surface impedance and absorption coefficients. In this work, a technique based on the equivalent source method (ESM) is used to estimate the pressure and velocity field in order to compute the surface impedance and reflection coefficient of a locally reacting surface. The assessed in-situ technique only requires measuring on a single layer with an array of pressure-velocity (p-u) probes. A numerical simulation study is performed to compare the estimated values with those obtained using a double layer of pressure sensors. Results show a significant improvement in the lower frequency range in terms of both reconstruction accuracy and robustness against noise.
Carrillo Pousa, G., Fernandez Comesana, D., Prieto, A. and Perez Cabo, D., 2016. Numerical study of an in-situ technique for measuring surface impedance and reflection coefficient of a locally reacting material with pressure-velocity probes. In INTER-NOISE and NOISE-CON Congress and Conference Proceedings (Vol. 252, No. 2, pp. 53-61). Institute of Noise Control Engineering.