Hydrodynamic Load Benchmarking on Bottom-Seated Cylinders in Finite Depths: A Frequency-Domain Comparison of Analytical and Open-Source BEM Solutions

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Published: Jul 30, 2024
DOI: https://doi.org/10.12681/ta.40045
Keywords:
Exciting wave forces added mass hydrodynamic damping mean second-order wave drift forces RAOs analytical solution BEM methods
Sarantos Sarantidis
Department of Naval Architecture, School of Engineering, University of West Attica
https://orcid.org/0009-0005-5446-7073
Thomas P. Mazarakos
Department of Naval Architecture, School of Engineering, University of West Attica
Abstract

The scope of the presented paper is a benchmark study between the results of analytical and Boundary Element Method (BEM) solutions for the hydrodynamic problem of a vertical fixed cylinder due to the action of linear waves. First-order hydrodynamic exciting wave forces and moments, added mass, hydrodynamic damping coefficients, and the Response Amplitude Operators (RAOs) for the surge motion are calculated. The mean second-order wave drift forces are also given by using the direct integration method. The analytical solution is calculated in the frequency domain for a wide range of frequencies for different cylinder characteristics. Finite water depths and linear waves are considered. Therefore, a formulation of the problem based on the Laplace equation and boundary conditions on the free surface and seabed, is given. Also, two different open-source BEM codes are used to solve the hydrodynamic problem. The calculated results are compared to those of other investigators' analytical and numerical predications.

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  • Naval Coastal and Maritime Design Engineering and Planning
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