A new method for the calculation of wave radiation stress is proposed by linking the expressions for wave radiation stress with the variables in the parabolic mild slope equation. The governing equations are solved nu...A new method for the calculation of wave radiation stress is proposed by linking the expressions for wave radiation stress with the variables in the parabolic mild slope equation. The governing equations are solved numerically by the finite difference method. Numerical results show that the new method is accurate enough, can be efficiently solved with little programming effort, and can be applied to the calculation of wave radiation stress for large coastal areas.展开更多
The 'surface roller' to simulate wave energy dissipation of wave breaking is introduced into the random wave model based on approximate parabolic mild slope equation in this paper to simulate the random wave t...The 'surface roller' to simulate wave energy dissipation of wave breaking is introduced into the random wave model based on approximate parabolic mild slope equation in this paper to simulate the random wave transportation in chiding diffraction, refraction and breaking in nearshore areas. The roller breaking random wave higher-order approximate parabolic equation model has been verified by the existing experimental data for a plane slope beach and a circular shoal, and the numerical results of random wave breaking model agree with the experimental data very well, This model can be applied to calculate random wave propagation from deep to shallow water in large areas near the shore over natural topography.展开更多
This paper presents a numerical model study of the propagation of water waves using the parabolic approximation of the mild slope equation in the orthogonal coordinate system. Two types of coordinate systems are stud...This paper presents a numerical model study of the propagation of water waves using the parabolic approximation of the mild slope equation in the orthogonal coordinate system. Two types of coordinate systems are studied: (a) a general form of orthogonal coordinate system and (b) the conformal system, a special form of orthogonal coordinate system. Two typical examples, namely, expanded breakwaters and a circular channel, are studied to validate the model. First, the examples are studied by use of the general orthogonal coordinates. Then the same examples are computed by use of the conformal system. The computational results show that the conformal coordinate system generally gives better predictions than the general orthogonal system. A numerical technique for generating the conformal grid is combined with the numerical model to improve the practicability of the model. The comparison between the result from the numerical grid system and that from the analytical grid system shows that reliable computational results can be obtained by use of the numerical conformal grid system.展开更多
The split-step pseudo-spectral method is a useful method for solving nonlinear wave equations. However, it is not widely used because of the limitation of the periodic boundary condition. In this paper, the method is ...The split-step pseudo-spectral method is a useful method for solving nonlinear wave equations. However, it is not widely used because of the limitation of the periodic boundary condition. In this paper, the method is modified at its second step by avoiding transforming the wave height function into a frequency domain function. Thus, the periodic boundary condition is not required, and the new method is easy to implement. In order to validate its performance, the proposed method was used to solve the nonlinear parabolic mild-slope equation and the spatial modified nonlinear Schrodinger （MNLS） equation, which were used to model the wave propagation under different bathymetric conditions. Good agreement between the numerical and experimental results shows that the present method is effective and efficient in solving nonlinear wave eouations.展开更多
利用抛物型缓坡方程计算波浪场,并以波浪辐射应力为近岸动力因素,建立深度平均的二维近岸流的控制方程。运用该近岸流方程,对美国Santa Barbara Leadbetter海岸波浪斜向入射所产生的波浪场及波浪破碎所形成的沿岸流进了数值模拟,其中抛...利用抛物型缓坡方程计算波浪场,并以波浪辐射应力为近岸动力因素,建立深度平均的二维近岸流的控制方程。运用该近岸流方程,对美国Santa Barbara Leadbetter海岸波浪斜向入射所产生的波浪场及波浪破碎所形成的沿岸流进了数值模拟,其中抛物型缓坡模型采用Crank-Nicolson格式进行数值离散,近岸流方程采用ADI差分格式离散。与现场实测资料的对比表明,无论考虑或不考虑波浪非线性因子,模拟结果与实测结果均吻合良好。展开更多
将适用于近岸较大区域波浪传播变形的三种模型,即基于抛物型缓坡方程的不规则波模型、引入浅水波浪谱TMA谱的SWAN(simulating waves nearshore)模型以及采用默认JONSWAP谱的SWAN模型应用于特拉华大学(University of Delaware)圆形浅滩...将适用于近岸较大区域波浪传播变形的三种模型,即基于抛物型缓坡方程的不规则波模型、引入浅水波浪谱TMA谱的SWAN(simulating waves nearshore)模型以及采用默认JONSWAP谱的SWAN模型应用于特拉华大学(University of Delaware)圆形浅滩实验进行比较。结果显示,抛物型缓坡方程和SWAN的模拟结果与实验所测数据符合都比较好;SWAN在非线性作用较强的浅滩中心及靠后部效果更佳,而抛物型缓坡方程由于没有考虑非线性作用,模拟得到的最大波高较实测值偏高,且波高变化较为剧烈。展开更多
基金This subject was financially supported by the National Natural Science Foundation of China(Grant No.59839330 and No.49910161985)
文摘A new method for the calculation of wave radiation stress is proposed by linking the expressions for wave radiation stress with the variables in the parabolic mild slope equation. The governing equations are solved numerically by the finite difference method. Numerical results show that the new method is accurate enough, can be efficiently solved with little programming effort, and can be applied to the calculation of wave radiation stress for large coastal areas.
基金This work was financially supported by the National Natural Science Foundation of China(Grant No.59839330 and No.19772031)
文摘The 'surface roller' to simulate wave energy dissipation of wave breaking is introduced into the random wave model based on approximate parabolic mild slope equation in this paper to simulate the random wave transportation in chiding diffraction, refraction and breaking in nearshore areas. The roller breaking random wave higher-order approximate parabolic equation model has been verified by the existing experimental data for a plane slope beach and a circular shoal, and the numerical results of random wave breaking model agree with the experimental data very well, This model can be applied to calculate random wave propagation from deep to shallow water in large areas near the shore over natural topography.
文摘This paper presents a numerical model study of the propagation of water waves using the parabolic approximation of the mild slope equation in the orthogonal coordinate system. Two types of coordinate systems are studied: (a) a general form of orthogonal coordinate system and (b) the conformal system, a special form of orthogonal coordinate system. Two typical examples, namely, expanded breakwaters and a circular channel, are studied to validate the model. First, the examples are studied by use of the general orthogonal coordinates. Then the same examples are computed by use of the conformal system. The computational results show that the conformal coordinate system generally gives better predictions than the general orthogonal system. A numerical technique for generating the conformal grid is combined with the numerical model to improve the practicability of the model. The comparison between the result from the numerical grid system and that from the analytical grid system shows that reliable computational results can be obtained by use of the numerical conformal grid system.
基金supported by the Central Public-Interest Scientific Institution Basal Research Fund of China(Grant No.TKS100108)
文摘The split-step pseudo-spectral method is a useful method for solving nonlinear wave equations. However, it is not widely used because of the limitation of the periodic boundary condition. In this paper, the method is modified at its second step by avoiding transforming the wave height function into a frequency domain function. Thus, the periodic boundary condition is not required, and the new method is easy to implement. In order to validate its performance, the proposed method was used to solve the nonlinear parabolic mild-slope equation and the spatial modified nonlinear Schrodinger （MNLS） equation, which were used to model the wave propagation under different bathymetric conditions. Good agreement between the numerical and experimental results shows that the present method is effective and efficient in solving nonlinear wave eouations.
文摘利用抛物型缓坡方程计算波浪场,并以波浪辐射应力为近岸动力因素,建立深度平均的二维近岸流的控制方程。运用该近岸流方程,对美国Santa Barbara Leadbetter海岸波浪斜向入射所产生的波浪场及波浪破碎所形成的沿岸流进了数值模拟,其中抛物型缓坡模型采用Crank-Nicolson格式进行数值离散,近岸流方程采用ADI差分格式离散。与现场实测资料的对比表明,无论考虑或不考虑波浪非线性因子,模拟结果与实测结果均吻合良好。
文摘将适用于近岸较大区域波浪传播变形的三种模型,即基于抛物型缓坡方程的不规则波模型、引入浅水波浪谱TMA谱的SWAN(simulating waves nearshore)模型以及采用默认JONSWAP谱的SWAN模型应用于特拉华大学(University of Delaware)圆形浅滩实验进行比较。结果显示,抛物型缓坡方程和SWAN的模拟结果与实验所测数据符合都比较好;SWAN在非线性作用较强的浅滩中心及靠后部效果更佳,而抛物型缓坡方程由于没有考虑非线性作用,模拟得到的最大波高较实测值偏高,且波高变化较为剧烈。
