A Chebyshev-Tau Spectral Method for Coupled Modes of Underwater Sound Propagation in Range-Dependent Ocean Environments

TL;DR

This paper introduces a Chebyshev-Tau spectral method-based algorithm for solving coupled modes in range-dependent underwater sound propagation, offering improved stability, efficiency, and accuracy over traditional methods in complex ocean environments.

Contribution

The paper develops a novel spectral algorithm using Chebyshev--Tau methods with parallelization, enhancing stability and efficiency for coupled-mode sound propagation in complex, range-dependent ocean settings.

Findings

The new algorithm is more stable and efficient than existing programs.

Numerical simulations confirm high accuracy and reliability.

The method effectively handles complex ocean environments.

Abstract

The stepwise coupled-mode model is a classic approach for solving range-dependent sound propagation problems. Existing coupled-mode programs have disadvantages such as high computational cost, weak adaptability to complex ocean environments and numerical instability. In this paper, a new algorithm is designed that uses an improved range normalization and global matrix approach to address range dependence in ocean environments. Due to its high accuracy in solving differential equations, the spectral method has recently been applied to range-independent normal modes and has achieved remarkable results. This algorithm uses the Chebyshev--Tau spectral method to solve for the eigenmodes in the range-independent segments. The main steps of the algorithm are parallelized, so OpenMP multithreading technology is also applied for further acceleration. Based on this algorithm, an efficient program is developed, and numerical simulations verify that this algorithm is reliable, accurate and capable. Compared with the existing coupled-mode programs, the newly developed program is more stable and efficient at comparable accuracies and can solve waveguides in more complex and realistic ocean environments.