CALCULATION OF THE SOUND FIELD IN A WAVE-GUIDE WITH A LAYERED ABSORBING BOTTOM

This paper describes a procedure for calculation of the sound field in a plain layered absorptive waveguide by the normal mode technique. Th e eigenvalues and eigenfunction of the waveguide are found using the f inite-difference approximation to the differential spectral problem. S pecial attention is paid to the approximation used to match the eigenf unctions at the boundaries of adjacent layers. The performance of the algorithm is illustrated by some numerical tests and experimental exam ples.