4.2. Liner impedance eduction procedure
Normalised impedance values for the liner have been educed from the pressure data by Jones et al. [11] using a 2D finite element method (FEM)-based procedure. In addition to using these Jones et al. educed liner impedance values, impedance values have also been educed here to best-fit the Jones et al. complex pressure data using the WEM-based methodology. This is achieved, in the same way as used by Jones et al. for consistency, by iteratively minimising the objective function