Finite Difference Time Domain Analysis for a Sound Field Including a Plate in Water

Abstract

In marine research, measures against self-noise of an observatory ship are important. Generally, the self-noise is measured after the completion of ships. It is difficult to predict this noise level beforehand. Then, an attempt is made to determine the noise emitted from various elements of a structure. The finite difference time domain method is applied to obtain sound fields, including that of a plate in water. The time behavior of the sound wave emitted from a sound source placed near the upper part of a plate is investigated. As a result, the reflected and re-radiated waves from the plate including the head wave resulting from the longitudinal and traverse waves in the plate are able to be visualized. In the case of the plate with a branch plate, the suppression of the wave which propagates at the inside of the plate with the length of the branch plate is shown.

A Review on Deep Learning-Based Approaches for Automatic Sonar Target Recognition

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A Finite-Difference Time-Domain Technique for Nonlinear Elastic Media and Its Application to Nonlinear Lamb Wave Propagation

“…There have recently been a number of studies of elastodynamic problems using the finite-difference time-domain (FDTD) method [1][2][3][4][5][6] . This method is also referred to as the velocity-stress finite-difference or staggered grid finite-difference formulation 7) , where Navier's equations are decomposed to a set of first-order partial differential equations with respect to velocity and stress.…”

A Finite-Difference Time-Domain Technique for Nonlinear Elastic Media and Its Application to Nonlinear Lamb Wave Propagation

“…There have recently been a number of studies of elastodynamic problems using the finite-difference time-domain (FDTD) method. [1][2][3][4][5][6] This method is also referred to as the velocity-stress finite-difference or staggered grid finitedifference formulation, 7) where Navier's equations are decomposed to a set of first-order partial differential equations with respect to velocity and stress. The staggered grid finite-difference formulation has practical advantage for its stability and accuracy.…”