Numerical simulation study on influences of onshore wind on overtopping characteristics of solitary wave under coastal seawall

ZHANG Liangbin, QU Ke, HUANG Jingxuan, WANG Xu, GUO Lei

Journal of Marine Sciences ›› 2023, Vol. 41 ›› Issue (4) : 32-45.

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Journal of Marine Sciences ›› 2023, Vol. 41 ›› Issue (4) : 32-45. DOI: 10.3969-j.issn.1001-909X.2023.04.004

Numerical simulation study on influences of onshore wind on overtopping characteristics of solitary wave under coastal seawall

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Abstract

Seawalls play an important role in protecting coastal towns from extreme waves damage. Based on two-dimensional incompressible two-phase flow numerical model, the influences of onshore wind on overtopping characteristics of solitary wave under coastal seawall were systematically studied in this paper. The reliability of the numerical model was verified by comparing the numerical results with experimental data, and the influencing factors such as onshore wind speed, incident wave height, crest freeboards of the coastal seawall, beach slope and seawall slope on the hydrodynamic process of solitary wave overtopping of coastal seawalls were discussed in detail. The research results show that with the increase of onshore wind speed, incident wave height and the decrease of crest freeboards of the coastal seawall, the maximum overtopping volume, maximum runup height and spatial distributions of the maximum water elevation gradually increase. With the increase of beach slope and seawall slope, the maximum overtopping volume increase and decrease, respectively, while the maximum runup height gradually increase. Onshore wind can affect the hydrodynamic characteristics of solitary wave overtopping of coastal seawall, increase the wave steepness and the wave crest propagation speed and cause the wave breaking earlier. Compared with the windless condition, the maximum wave overtopping volume, maximum runup height, maximum hydrodynamic forces and spatial distributions of the maximum water elevation are increased under onshore wind. The results of this study can provide a reference for the design of coastal engineering.

Key words

solitary wave / onshore wind / overtopping volume / numerical simulation / hydrodynamic characteristics

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ZHANG Liangbin , QU Ke , HUANG Jingxuan , et al . Numerical simulation study on influences of onshore wind on overtopping characteristics of solitary wave under coastal seawall[J]. Journal of Marine Sciences. 2023, 41(4): 32-45 https://doi.org/10.3969-j.issn.1001-909X.2023.04.004

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