Long wave interaction with a partially immersed body. Part II: Numerical results

Gayaz Khakimzyanov; Denys Dutykh; Oleg Gusev

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arXiv · 2204.08210

Long wave interaction with a partially immersed body. Part II: Numerical results

Gayaz Khakimzyanov·Denys Dutykh·Oleg Gusev

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Abstract

In this manuscript we perform an extensive numerical study of the long wave interaction problem with a fixed partially immersed body into a fluid layer. The incident wave is assumed to be an isolated solitary wave. The body in this study is assumed to be fixed with a rectangular section which is not touching the bottom of the channel. The mathematical modelling of this problem is based on Part I (Khakimzyanov and Dutykh 2020) of this series and considered models include the Nonlinear Shallow Water Equations (NSWE), fully nonlinear weakly dispersive Serre-Green-Naghdi Equations (SGN equations) (completed with appropriate compatibility conditions on solid/fluid boundaries) and the free surface irrotational full Euler equations (FEE). We study the influence of the floating body elongation, immersion depth and incident wave amplitude on the wave field before and after the obstacle. The comparison of all three models predictions and the data of small-scale laboratory experiments is performed. Moreover, in the framework of the FEE model we investigate the anomalous wave run-up behind the floating body in the close presence of a vertical wall. We demonstrate the cases where the vertical wall creates extreme wave amplitudes behind the body, but also we show the cases where the wall attenuates wave amplitudes comparing to the wave field without a wall.

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Gayaz Khakimzyanov, Denys Dutykh, Oleg Gusev. 2022-04-18. Long wave interaction with a partially immersed body. Part II: Numerical results. https://arxiv.org/abs/2204.08210

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