Numerical simulation of the influence of submerged artificial structures on hydrodynamic characteristics and run-up of solitary waves over shore reefs

doi:10.3969/j.issn.1001-909X.2025.01.010

Abstract

Abstract:

Global warming has led to rising sea levels and weakened the ability of natural barriers such as coral reefs to withstand extreme disasters like hurricanes and tsunamis. Therefore, artificial barriers, such as seawalls or submerged structures, need to be deployed near coasts to effectively protect shoreline areas. This study aims to investigate the hydrodynamic effects of submerged artificial structures on the propagation and deformation of solitary waves over reefs through numerical simulation. A high-precision wave numerical flume was established using the non-hydrostatic model NHWAVE, and the model was validated with experimental data. The study focused on analyzing the impacts of factors such as incident wave height, reef flat water depth, slope of artificial structure, peak width of artificial structures, and slope of the fore reef on hydrodynamic characteristics of solitary waves. Results show that the presence of submerged artificial structure increases wave reflection coefficients and induces vortex formation between waves and water, and the complex flow field can effectively dissipate part of the incident wave energy, which has a mitigating effect on the amplitude and climbing height of the solitary wave. The results of this study can provide a valuable reference for the design of submerged artificial structures.

Key words: solitary wave, numerical simulation, shore reef, submerged artificial structure, non-hydrostatic model, hydrodynamic properties

CLC Number:

U656.314

ZHU Lunjia, QU Ke, WANG Xu, WANG Chao, LI Tiankuo. Numerical simulation of the influence of submerged artificial structures on hydrodynamic characteristics and run-up of solitary waves over shore reefs[J]. Journal of Marine Sciences, 2025, 43(1): 107-121.

Figures/Tables 22

Fig.1 Calculation area layout of numerical simulation of shore reefs without artificial structure

Fig.2 Time series validation of water elevation at different wave gauges on shore reefs without artificial structure

Fig.3 Time series validation of solitary wave run-up on shore reefs without artificial structure

Fig.4 Calculation area layout of numerical flume for submerged embankment

Fig.5 Time series validation of water elevation at different wave gauges on a submerged dyke reef

Fig.6 Calculation area layout of numerical flume for shore reefs with submerged artificial structure

Tab.1 Parameter setup of numerical simulation

工况	入射波高/m	礁坪水深/m	结构物坡度	结构物峰宽/m	结构物峰高/m	礁前斜坡坡度	工况	入射波高/m	礁坪水深/m	结构物坡度	结构物峰宽/m	结构物峰高/m	礁前斜坡坡度
A1	0.063 45	0.040				1∶5	D4	0.105 75	0.080	1∶1.25	0.040	0.360	1∶5
A2	0.084 60	0.040				1∶5	D5	0.105 75	0.100	1∶1.25	0.040	0.360	1∶5
A3	0.105 75	0.040				1∶5	E1	0.105 75	0.040	1∶0.25	0.040	0.360	1∶5
A4	0.126 90	0.040				1∶5	E2	0.105 75	0.040	1∶0.75	0.040	0.360	1∶5
A5	0.148 05	0.040				1∶5	E3	0.105 75	0.040	1∶1.75	0.040	0.360	1∶5
B1	0.063 45	0.040	1∶1.25	0.040	0.360	1∶5	E4	0.105 75	0.040	1∶2.25	0.040	0.360	1∶5
B2	0.084 60	0.040	1∶1.25	0.040	0.360	1∶5	F1	0.105 75	0.040	1∶1.25	0.000	0.360	1∶5
B3	0.105 75	0.040	1∶1.25	0.040	0.360	1∶5	F2	0.105 75	0.040	1∶1.25	0.020	0.360	1∶5
B4	0.126 90	0.040	1∶1.25	0.040	0.360	1∶5	F3	0.105 75	0.040	1∶1.25	0.060	0.360	1∶5
B5	0.148 05	0.040	1∶1.25	0.040	0.360	1∶5	F4	0.105 75	0.040	1∶1.25	0.080	0.360	1∶5
C1	0.105 75	0.000				1∶5	G1	0.105 75	0.040				1∶3
C2	0.105 75	0.020				1∶5	G2	0.105 75	0.040				1∶4
C3	0.105 75	0.060				1∶5	G3	0.105 75	0.040				1∶6
C4	0.105 75	0.080				1∶5	G4	0.105 75	0.040				1∶7
C5	0.105 75	0.100				1∶5	H1	0.105 75	0.040	1∶1.25	0.040	0.360	1∶3
D1	0.105 75	0.000	1∶1.25	0.040	0.360	1∶5	H2	0.105 75	0.040	1∶1.25	0.040	0.360	1∶4
D2	0.105 75	0.020	1∶1.25	0.040	0.360	1∶5	H3	0.105 75	0.040	1∶1.25	0.040	0.360	1∶6
D3	0.105 75	0.060	1∶1.25	0.040	0.360	1∶5	H4	0.105 75	0.040	1∶1.25	0.040	0.360	1∶7

Fig.7 Wave velocity clouds at different moments on shore reefs with and without artificial structure

Fig.8 Comparative time series of water elevation at different wave gauges on shore reefs with and without artificial structure

Fig.9 Distributions of maximum wave height along shore reefs with and without artificial structure

Fig.10 Flow field and vorticity distribution at different time instants along shore reefs with artificial structure

Fig.11 Wave run-up temporal evolution on shore reefs with and without artificial structure

Fig.12 Along-track distributions of maximum wave heights along shore reefs with and without artificial structure under different incident wave heights

Fig.13 Variation of maximum drop in local wave height near artificial structure under different incident wave heights

Fig.14 Along-track distributions of maximum wave heights along shore reefs with and without artificial structure under different reef flat water depths

Fig.15 Variation of maximum drop in local wave height near artificial structure under different reef flat water depths

Fig.16 Along-track distribution of maximum wave heights under different artificial structure slopes (a) and variation of maximum drop in local wave height in the vicinity of artificial structure (b)

Fig.17 Along-track distribution of maximum wave heights under different peak widths of artificial structure (a) and variation of maximum local wave height drop near artificial structure (b)

Fig.18 Along-track distribution of maximum wave heights along shore reef with and without artificial structure under different reef front slope gradients

Fig.19 Variation of maximum drop in local wave height near artificial structure with different reef front slope gradients

Fig.20 Variations of the reflection coefficient CR under different operating conditions on shore reefs with and without artificial structure

Fig.21 Variation of the maximum wave run-up Rup,max under different operating conditions on shore reefs with and without artificial structure

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