A computational method for the fluid-structure interaction in nonlinear ocean waves using the nonlinear Schrödinger equation

An efficient computation of the fluid-structure interaction (FSI) between mechanical structures and ocean waves is an important topic for many applications in ocean engineering and naval architecture. For many of such applications, it is often sufficient to consider the FSI within the potential flow theory instead of using the Navier-Stokes equations. However, the numerical solution of the governing equations of the potential flow theory is still computationally expensive. This work contributes to the improvement of the currently available numerical schemes, which compute the FSI in nonlinear ocean waves. The approach used in this work is based on the nonlinear Schrödinger equation (NLS). Compared to the governing equations of potential flow theory, solutions of the NLS can be computed much more efficiently. This efficiency advantage is used to develop a method that allows a fast computation of the FSI in nonlinear water waves. The developed method is investigated with regard to its accuracy, application areas, and computational effort. Here, numerical results for the hydrodynamic forces acting on mechanical structures and the resulting motion of the structures are analyzed. It is found that the NLS offers an interesting possibility to efficiently investigate the behavior of structures excited by nonlinear ocean waves.

Subjects

Nonlinear Schrödinger equation

Computational method

Fluid-structure interaction

Ocean waves

Irregular sea

DDC Class

620.1: Engineering Mechanics and Materials Science

Funding(s)

Projekt DEAL

Lizenz

https://creativecommons.org/licenses/by/4.0/

Publication version

publishedVersion

Name

1-s2.0-S0029801825031014-main.pdf

Size

4.19 MB

Format

Adobe PDF

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A computational method for the fluid-structure interaction in nonlinear ocean waves using the nonlinear Schrödinger equation