Influence of Relative Water Depth on Wave Run-up Over Costal Structures; Smooth Slopes

This paper presents the results from a comprehensive experimental study on the Quadrant Face Pile Supported Breakwater (QPSB) in two different water depths exposed to three different oblique wave attacks. The results are compared with that for a Vertical face Pile Supported Breakwater (VPSB) for identical test conditions. The paper compares the reflection coefficient, transmission coefficient, energy loss coefficient, non-dimensional pressure, and non-dimensional run-up as a function of the relative water depth and scattering parameter. The results obtained for QPSB are validated with existing results. The salient observations show that QPSB experiences better hydrodynamic performance characteristics than the VPSB under oblique waves.

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Wave Scattering From Multiple Horizontal Plates as a Breakwater

Volume 4: Ocean Engineering; Ocean Renewable Energy; Ocean Space Utilization, Parts A and B ◽

10.1115/omae2009-79276 ◽

2009 ◽

Author(s):

Guoyu Wang ◽

Yongxue Wang

Keyword(s):

Water Depth ◽

Plate Thickness ◽

Wave Theory ◽

Linear Potential ◽

Antisymmetric Part ◽

Transmission Coefficients ◽

Present Solution ◽

Relative Water ◽

Constant Coefficients ◽

Finite Water Depth

The multiple horizontal plates breakwater is proposed in this article, which mainly consists of several horizontal plates. The regular wave test results demonstrate that it has good performance of dissipating waves. Based on the linear potential wave theory, the scattering of waves normally incident on the multiple horizontal plates in a channel of finite water depth is investigated. The velocity potential is split to the symmetric and antisymmetric part, and the method of eigenfunction expansions is used to obtain the unknown constant coefficients determined from the matching conditions. The thickness of the plates is considered in the theoretical analysis. The present solution is compared with the existing theoretical, numerical and experimental results with good agreements. The parameters such as the relative water depth, relative plate width, relative plate thickness and number of plates, those identified with the performance of the breakwater are investigated and discussed. The variation of reflection and transmission coefficients alone with the above mentioned parameters are also presented.

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Three-Dimensional Turbulence Numerical Simulation of Flow in a Stepped Dropshaft

Water ◽

10.3390/w11010030 ◽

2018 ◽

Vol 11 (1) ◽

pp. 30 ◽

Cited By ~ 1

Author(s):

Yongfei Qi ◽

Yurong Wang ◽

Jianmin Zhang

Keyword(s):

Flow Pattern ◽

Water Depth ◽

Three Dimensional ◽

Drainage System ◽

Urban Drainage ◽

Pipe Network ◽

Central Angle ◽

Relative Water ◽

Maximum Water ◽

Horizontal Step

The dropshaft structure is usually applied in an urban drainage system to connect the shallow pipe network and the deep tunnel. By using the renormalization group (RNG) k~ε turbulence model with a volume of fluid method, the flow pattern and the maximum relative water depth over a stepped dropshaft with a different central angle of step were numerically investigated. The calculated results suggested that the flow in the stepped dropshaft was highly turbulent and characterized by deflection during the jet caused by the curvature of the sidewall. According to the pressure distribution on the horizontal step and the flow pattern above the step, the flow field was partitioned into the recirculating region, the wall-impinging region and the mixing region. In addition, with the increase in the central angle of step, the scope of the wall-impinging region and the mixing region increased and the scope of the recirculating region remained nearly unchanged. The maximum water depth increased with the increase in discharge. In the present work we have shown that, as the value of the central angle of step increased, the maximum water depth decreased initially and increased subsequently.

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LARGE SCALE EXPERIMENTS ON EVOLUTION AND RUN-UP OF BREAKING SOLITARY WAVES

Journal of Earthquake and Tsunami ◽

10.1142/s1793431107000158 ◽

2007 ◽

Vol 01 (03) ◽

pp. 257-272 ◽

Cited By ~ 3

Author(s):

KAO-SHU HWANG ◽

YU-HSUAN CHANG ◽

HWUNG-HWENG HWUNG ◽

YI-SYUAN LI

Keyword(s):

Solitary Wave ◽

Wave Height ◽

Solitary Waves ◽

Water Depth ◽

Large Scale ◽

Scale Effects ◽

Wave Heights ◽

Run Up ◽

Hydraulics Laboratory ◽

The Waves

The evolution and run-up of breaking solitary waves on plane beaches are investigated in this paper. A series of large-scale experiments were conducted in the SUPER TANK of Tainan Hydraulics Laboratory with three plane beaches of slope 0.05, 0.025 and 0.017 (1:20, 1:40 and 1:60). Solitary waves of which relative wave heights, H/h0, ranged from 0.03 to 0.31 were generated by two types of wave-board displacement trajectory: the ramp-trajectory and the solitary-wave trajectory proposed by Goring (1979). Experimental results show that under the same relative wave height, the waveforms produced by the two generation procedures becomes noticeably different as the waves propagate prior to the breaking point. Meanwhile, under the same relative wave height, the larger the constant water depth is, the larger the dimensionless run-up heights would be. Scale effects associated with the breaking process are discussed.

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Frequency analysis of wave run-up on vertical cylinder in transitional water depth

Ocean Systems Engineering ◽

10.12989/ose.2014.4.3.201 ◽

2014 ◽

Vol 4 (3) ◽

pp. 201-213

Author(s):

Yanfei Deng ◽

Jianmin Yang ◽

Longfei Xiao ◽

Yugao Shen

Keyword(s):

Frequency Analysis ◽

Water Depth ◽

Vertical Cylinder ◽

Run Up

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EFFECT OF WATER DEPTH AND SURFACE ROUGHNESS ON WAVE RUN-UP

Coastal Engineering 2004 ◽

10.1142/9789812701916_0351 ◽

2005 ◽

Author(s):

JANAKA J. WIJETUNGE

Keyword(s):

Surface Roughness ◽

Water Depth ◽

Effect Of Water ◽

Run Up

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A simple stress-based cliff-calving law

The Cryosphere ◽

10.5194/tc-13-2475-2019 ◽

2019 ◽

Vol 13 (9) ◽

pp. 2475-2488 ◽

Cited By ~ 1

Author(s):

Tanja Schlemm ◽

Anders Levermann

Keyword(s):

Stress Field ◽

Yield Stress ◽

Sea Level ◽

Water Depth ◽

Stability Limit ◽

Two Dimensional ◽

Loss Mechanism ◽

Relative Water ◽

Ice Failure ◽

Dry Water

Abstract. Over large coastal regions in Greenland and Antarctica the ice sheet calves directly into the ocean. In contrast to ice-shelf calving, an increase in calving from grounded glaciers contributes directly to sea-level rise. Ice cliffs with a glacier freeboard larger than ≈100 m are currently not observed, but it has been shown that such ice cliffs are increasingly unstable with increasing ice thickness. This cliff calving can constitute a self-amplifying ice loss mechanism that may significantly alter sea-level projections both of Greenland and Antarctica. Here we seek to derive a minimalist stress-based parametrization for cliff calving from grounded glaciers whose freeboards exceed the 100 m stability limit derived in previous studies. This will be an extension of existing calving laws for tidewater glaciers to higher ice cliffs. To this end we compute the stress field for a glacier with a simplified two-dimensional geometry from the two-dimensional Stokes equation. First we assume a constant yield stress to derive the failure region at the glacier front from the stress field within the glacier. Secondly, we assume a constant response time of ice failure due to exceedance of the yield stress. With this strongly constraining but very simple set of assumptions we propose a cliff-calving law where the calving rate follows a power-law dependence on the freeboard of the ice with exponents between 2 and 3, depending on the relative water depth at the calving front. The critical freeboard below which the ice front is stable decreases with increasing relative water depth of the calving front. For a dry water front it is, for example, 75 m. The purpose of this study is not to provide a comprehensive calving law but to derive a particularly simple equation with a transparent and minimalist set of assumptions.

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Physical and Numerical Investigations on Wave Run-Up and Dissipation under Breakwater with Fence Revetment

Journal of Marine Science and Engineering ◽

10.3390/jmse9121355 ◽

2021 ◽

Vol 9 (12) ◽

pp. 1355

Author(s):

Enjin Zhao ◽

Lin Mu ◽

Zhaoyang Hu ◽

Xinqiang Wang ◽

Junkai Sun ◽

...

Keyword(s):

Wave Height ◽

Water Depth ◽

Significant Wave Height ◽

Irregular Waves ◽

Structure Stability ◽

Wave Impact ◽

Significant Wave ◽

Tide Level ◽

Run Up ◽

The Impact

Revetment elements and protective facilities on a breakwater can effectively weaken the impact of waves. In order to resist storm surges, there is a plan to build a breakwater on the northern shore of Meizhou Bay in Putian City, China. To better design it, considering different environmental conditions, physical and numerical experiments were carried out to accurately study the effects of the breakwater and its auxiliary structures on wave propagation. In the experiments, the influence of the wave type, initial water depth, and the structure of the fence plate are considered. The wave run-up and dissipation, the wave overtopping volume, and the structure stability are analyzed. The results indicate that the breakwater can effectively resist the wave impact, reduce the wave run-up and overtopping, and protect the rear buildings. In addition, under the same still water depth and significant wave height, the amount of overtopped water under regular waves is larger than that under irregular waves. With the increase of the still water depth and significant wave height, the overtopped water increases, which means that when the storm surge occurs, damage on the breakwater under the high tide level is greater than that under the low tide level. Besides, the fence plate can effectively dissipate energy and reduce the overtopping volume by generating eddy current in the cavity. Considering the stability and the energy dissipation capacity of the fence plate, it is suggested that a gap ratio of 50% is reasonable.

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