Calculation of Normal Modes in Underwater Acoustic Propagation

This document introduces a normal mode calculation program for underwater acoustic propagation based on the Chebyshev approximation method. Normal modes refer to waves generated by object vibrations, which possess specific frequencies and waveform characteristics. The implementation utilizes Chebyshev polynomials to approximate the solution of the depth-dependent wave equation, providing higher computational accuracy for modal properties including phase velocity, group velocity, and modal amplitudes. The algorithm employs orthogonal polynomial expansion to handle boundary conditions and density variations in stratified media. This program is particularly suitable for researchers and engineers working on underwater acoustic propagation calculations in both scientific and industrial applications. Users can benefit from understanding fundamental principles of acoustic wave propagation while having the flexibility to modify the source code for various scenarios through parameter adjustments and boundary condition configurations. The code structure includes key functions for modal solution search, eigenvalue calculation, and field reconstruction. We hope this computational tool proves valuable for your underwater acoustics analysis!