This paper gives an overall discussion about water level change on slopes under wave action, including wave runup, wave rundown and wave up-down amplitude, and a suggested formula for their calculation.
To improve the current understanding of the reduction of tsunami-like solitary wave runup by the pile breakwater on a sloping beach, we developed a 3D numerical wave tank based on the CFD tool OpenFOAM in this study. ...To improve the current understanding of the reduction of tsunami-like solitary wave runup by the pile breakwater on a sloping beach, we developed a 3D numerical wave tank based on the CFD tool OpenFOAM in this study. The Navier Stokes equations were applied to solve the two-phase incompressible flow, combined with an LES model to solve the turbulence and a VOF method to capture the free surface. The adopted model was firstly validated with existing empirical formulas for solitary wave runup on the slope without the pile structure. It is then validated using our new laboratory observations of the free surface elevation, the velocity and the pressure around a row of vertical slotted piles subjected to solitary waves, as well as the wave runup on the slope behind the piles. Subsequently, a set of numerical simulations were implemented to analyze the wave reflection, the wave transmission, and the shoreline runup with various offshore wave heights, offshore water depths, adjacent pile spaces and beach slopes. Finally, an improved empirical equation accounting for the maximum wave runup on the slope was proposed by taking the presence of the pile breakwater into consideration.展开更多
The finite difference method and the volume of fluid (VOF) method were used to develop a three-dimensional numerical model to study wave interaction with a perforated caisson. The partial cell method was adopted to ...The finite difference method and the volume of fluid (VOF) method were used to develop a three-dimensional numerical model to study wave interaction with a perforated caisson. The partial cell method was adopted to solve this type of problem for the first time. The validity of the present model, with and without the presence of caisson structures, was examined by comparing the model results with experimental data. Then, the numerical model was used to investigate the effects of various wave and structure parameters on the wave force and wave runup of the perforated quasi-ellipse caisson. Compared with the solid quasi-ellipse caisson, the wave force on the perforated quasi-ellipse caisson is significantly reduced with increasing porosity of the perforated quasi-ellipse caisson. Furthermore, the perforated quasi-ellipse caisson can also reduce the wave runup, and it tends to decrease with the increase of the porosity of the perforated quasi-ellipse caisson and the relative wave height.展开更多
Coastal overwash is a natural phenomenon that commonly occurs during storm events and can cause considerable changes in nearshore morphology within a short time.In this study,a complete set of empirical overwash trans...Coastal overwash is a natural phenomenon that commonly occurs during storm events and can cause considerable changes in nearshore morphology within a short time.In this study,a complete set of empirical overwash transport algorithms is developed and introduced into a phase-averaged wave-current-sediment transport coupling model that integrates the Finite-Volume Community Ocean Model(FVCOM)and the Simulating Waves Nearshore(SWAN)model.The resulting morphological evolution model can simulate coastal overwash.Validation against the data obtained from multiple sets of laboratory overwash experiments demonstrates that the model performs relatively well in simulating morphological changes caused by runup overwash and inundation overwash under different hydrodynamic and beach profile conditions.The sensitivity of each empirical coefficient in the overwash transport algorithms is comprehensively analyzed.The effects of each coefficient on the output of the model are discussed,and a recommended value range is provided for each coefficient.展开更多
Based on the Navier-Stokes (N-S) equations for viscous, incompressible fluid and the VOF method, 2-D and 3-D Numerical Wave Tanks (NWT) for nonlinear shallow water waves are built. The dynamic mesh technique is ap...Based on the Navier-Stokes (N-S) equations for viscous, incompressible fluid and the VOF method, 2-D and 3-D Numerical Wave Tanks (NWT) for nonlinear shallow water waves are built. The dynamic mesh technique is applied, which can save computational resources dramatically for the simulation of solitary wave propagating at a constant depth. Higher order approximation for cnoidal wave is employed to generate high quality waves. Shoaling and breaking of solitary waves over different slopes are simulated and analyzed systematically. Wave runup on structures is also investigated. The results agree very well with experimental data or analytical solutions.展开更多
文摘This paper gives an overall discussion about water level change on slopes under wave action, including wave runup, wave rundown and wave up-down amplitude, and a suggested formula for their calculation.
基金financially supported by the National Natural Science Foundation of China(Grant Nos.51679014 and 51839002)the Hunan Science and Technology Plan Program(Grant No.2017RS3035)the Open Foundation of Key Laboratory of Key Technology on Hydropower Development of Hunan Province(Grant No.PKLHD201706)
文摘To improve the current understanding of the reduction of tsunami-like solitary wave runup by the pile breakwater on a sloping beach, we developed a 3D numerical wave tank based on the CFD tool OpenFOAM in this study. The Navier Stokes equations were applied to solve the two-phase incompressible flow, combined with an LES model to solve the turbulence and a VOF method to capture the free surface. The adopted model was firstly validated with existing empirical formulas for solitary wave runup on the slope without the pile structure. It is then validated using our new laboratory observations of the free surface elevation, the velocity and the pressure around a row of vertical slotted piles subjected to solitary waves, as well as the wave runup on the slope behind the piles. Subsequently, a set of numerical simulations were implemented to analyze the wave reflection, the wave transmission, and the shoreline runup with various offshore wave heights, offshore water depths, adjacent pile spaces and beach slopes. Finally, an improved empirical equation accounting for the maximum wave runup on the slope was proposed by taking the presence of the pile breakwater into consideration.
基金supported by the National Natural Science Foundation of China (Grant No. 50921001)the Science and Technology Program for Communications Construction in West China,of the Ministry of Transport of the People’s Republic of China (Grant No. 2004-328-832-51)
文摘The finite difference method and the volume of fluid (VOF) method were used to develop a three-dimensional numerical model to study wave interaction with a perforated caisson. The partial cell method was adopted to solve this type of problem for the first time. The validity of the present model, with and without the presence of caisson structures, was examined by comparing the model results with experimental data. Then, the numerical model was used to investigate the effects of various wave and structure parameters on the wave force and wave runup of the perforated quasi-ellipse caisson. Compared with the solid quasi-ellipse caisson, the wave force on the perforated quasi-ellipse caisson is significantly reduced with increasing porosity of the perforated quasi-ellipse caisson. Furthermore, the perforated quasi-ellipse caisson can also reduce the wave runup, and it tends to decrease with the increase of the porosity of the perforated quasi-ellipse caisson and the relative wave height.
基金This study is financially supported by the National Natural Science Foundation of China(Grant Nos.U1906231 and 51509183)the Tianjin Transportation Science and Technology Development Plan Project(Grant No.2020-12)the Fundamental Research Funds for the Central Public Welfare Research Institutes(Grant No.TKS20200410).
文摘Coastal overwash is a natural phenomenon that commonly occurs during storm events and can cause considerable changes in nearshore morphology within a short time.In this study,a complete set of empirical overwash transport algorithms is developed and introduced into a phase-averaged wave-current-sediment transport coupling model that integrates the Finite-Volume Community Ocean Model(FVCOM)and the Simulating Waves Nearshore(SWAN)model.The resulting morphological evolution model can simulate coastal overwash.Validation against the data obtained from multiple sets of laboratory overwash experiments demonstrates that the model performs relatively well in simulating morphological changes caused by runup overwash and inundation overwash under different hydrodynamic and beach profile conditions.The sensitivity of each empirical coefficient in the overwash transport algorithms is comprehensively analyzed.The effects of each coefficient on the output of the model are discussed,and a recommended value range is provided for each coefficient.
文摘Based on the Navier-Stokes (N-S) equations for viscous, incompressible fluid and the VOF method, 2-D and 3-D Numerical Wave Tanks (NWT) for nonlinear shallow water waves are built. The dynamic mesh technique is applied, which can save computational resources dramatically for the simulation of solitary wave propagating at a constant depth. Higher order approximation for cnoidal wave is employed to generate high quality waves. Shoaling and breaking of solitary waves over different slopes are simulated and analyzed systematically. Wave runup on structures is also investigated. The results agree very well with experimental data or analytical solutions.