共查询到20条相似文献，搜索用时 125 毫秒
1.
四叉树网格下的椭圆型缓坡方程数值模型研究 总被引：1，自引：1，他引：0
波浪是近岸海域关键的水动力因素之一。考虑到近岸地形复杂、波浪演化显著的特点,建立了四叉树网格体系下的椭圆型缓坡方程数值模型,采用有限体积法对模型进行数值离散,应用GPBiCG(m, n)算法求解离散后的控制方程。模型中根据波浪波长布局计算网格,生成多层次四叉树网格,对复杂计算域有较好的适应性,并且在离散和方程求解中无需引入形函数、不产生复杂的交叉项,节约了存储空间和计算时间。将模型成功应用于物理模型实验及Acapulco海湾的波浪场数值模拟,结果表明该模型能够准确、高效地模拟近岸波浪场,可为近岸波浪场的模拟提供一定的理论和技术支持。 相似文献
2.
3.
适于模拟不规则水域波浪的缓坡方程两种数值模型比较 总被引：1，自引：1，他引：0
本文分析比较了适于不规则水域波浪模拟的椭圆型缓坡方程两种数值模型。两种数值模型均采用有限体积法离散,分别基于四叉树网格和非结构化三角形网格建立。首先结合近岸缓坡地形上波浪传播的经典物理模型实验对两种数值模型分别进行了验证,并结合计算结果对比分析了两种模型的计算精度和效率。计算结果表明,两种数值模型均可有效地模拟近岸波浪的传播变形;相对非结构化三角形网格下的模型,基于四叉树网格建立的数值模型在数值离散和求解过程中无需引入形函数、不产生复杂的交叉项,离散简单,易于程序实现,且节约计算存储空间,计算效率高。 相似文献
4.
5.
6.
7.
建立基于四阶完全非线性Boussinesq水波方程的二维波浪传播数值模型。采用Kennedy等提出的涡粘方法模拟波浪破碎。在矩形网格上对控制方程进行离散,采用高精度的数值格式对离散方程进行数值求解。对规则波在具有三维特征地形上的传播过程进行了数值模拟,通过数值模拟结果与实验结果的对比,对所建立的波浪传播模型进行了验证。同时,为了考察非线性对波浪传播的影响,给出和上述模型具有同阶色散性、变浅作用性能但仅具有二阶完全非线性特征的波浪模型的数值结果。通过对比两个模型的数值结果以及实验数据,讨论非线性在波浪传播过程中的作用。研究结果表明,所建立的Boussinesq水波方程在深水范围内不但具有较精确的色散性和变浅作用性能,而且具有四阶完全非线性特征,适合模拟波浪在近岸水域的非线性运动。 相似文献
8.
非结构化网格下近岸波生流数值模拟 总被引：5，自引：2，他引：3
波浪破碎产生的近岸流是近岸海域关键的水动力因素之一。基于近岸波浪的椭圆型缓坡方程和二维近岸波生流方程,建立了非结构化网格下近岸波浪破碎形成的近岸流数值模型。数值模型中,在空间上采用有限体积法进行数值离散,在时间上采用欧拉向前格式数值离散。数值计算结果表明,该数值模型可以有效地模拟近岸波浪破碎产生的近岸流。 相似文献
9.
本文建立了大亚湾风暴潮涌浪传播数学模型,以任意多边形离散计算海区,每一多边形构成单元,以波浪运动学和动力学守恒方程模拟单元内能量传递,以风暴潮过程模拟边界入射波高过程,用风暴潮涌浪传播基本方程和波能缓坡方程结合模拟湾口巨浪向湾内的传播过程。通过分析大亚湾不同种类岸线反射系数的概率分布,并结合实测波高对模型进行率定,最终确定模型参数。将大亚湾特征点计算波高与统计推荐波高比较进行模型验证,结果显示SE向波高与H_(13%)推荐波高对应较好,可以用于大亚湾海区的波浪预报。计算当大亚湾口分别出现10年一遇、50年一遇及100年一遇的波高时,在E、ESE以及ES向入射波浪条件下大亚湾海域极值波高的分布。分别对风暴潮涌浪在不同类型岸线的爬高以及风暴潮涌浪传播对岸线的作用力进行计算。 相似文献
10.
多方向不规则波传播变形数值模拟 总被引：1，自引：1，他引：1
在推广的缓坡方程数学模型基础上建立了多方向不规则波数学模型，综合考虑了波浪折射、绕射、反射、底摩擦和风能输入等因素。基于线性波浪理论，将波浪方向谱在频率和方向上按等能量分割法离散后，分别计算各组成波的传播变形，再计算合成波要素。缓坡方程数学模型采用改进的ADI法求解，计算效率高，稳定性好。采用椭圆形浅滩不规则波模型试验结果和单突堤不规则波绕射理论解对数学模型进行了验证，数值模拟结果和试验值及理论解符合良好。利用该模型进行了某港港内波浪折射、绕射和反射的联合数值模拟，给出了合理的港内波高分布。 相似文献
11.
波浪谱形对不规则波数值模拟的影响 总被引：1，自引：0，他引：1
通过数值模拟分析了波浪谱形对不规则波浪数值模拟结果的影响.采用不同参数的JONSWAP谱模拟入射波要素,基于抛物型缓坡方程模拟不规则波浪的传播,分析了波浪谱形状对波浪数值模拟结果的影响.结果表明,采用抛物型缓坡方程模拟不规则波浪时,入射波浪谱形对模拟结果影响不明显;但由于模型中非线性项的影响,采用不规则波模拟的波高分布和采用规则波模拟的结果略有差别. 相似文献
12.
Due to their capability of correctly representing wave characteristics, the number of numerical models based on Navier–Stokes equation (NSE) models has recently increased remarkably. One of the key challenges of this type of wave model, however, is to minimize the wave re-reflection from the incident boundary. Many numerical techniques have been developed to deal with this problem, and previous studies have reported on internal wave makers that employ NSE. Research on generation and transformation of irregular waves using a three-dimensional NSE model, however, has begun very recently, and few studies have yet been reported. In this study, a three-dimensional numerical model was applied to generate irregular waves, and transformation of irregular waves was simulated in a numerical wave tank. The model was first verified by applying it to simple numerical tests in two dimensions. The model was then used to generate directional monochromatic and irregular waves in three dimensions. The numerical results were compared with the analytical solutions, and good agreement was observed. Finally, the model was applied to simulate the transformation of irregular waves over an uneven bottom geometry in a wave tank. 相似文献
13.
This paper presents the development of a generalized Boussinesq (gB) model for the periodic non-linear shallow-water waves. An incident cnoidal wave solution for the gB model is derived and applied to the wave simulation. A set of radiation boundary conditions is also established to transmit effectively the cnoidal waves out of the computational domain. The classical solutions of the second-order cnoidal waves are discussed within the content of the KdV equation and the generalized Boussinesq equations. An Euler's predictor-corrector finite-difference algorithm is used for numerical computation. The propagation of normally incident cnoidal waves in a channel is studied. The simulated wave profiles agree well with the analytical results. The temporal and spatial evolution of an obliquely incident cnoidal wave is also modelled. The phenomenon of Mach reflection is discussed. 相似文献
14.
15.
Regular and irregular wave forces acting on vertical walls are studied by a previously developed numerical model. The computed wave forces are compared with the available experimental data to verify the numerical model, and satisfactory agreements are obtained. The variation of wave forces with incident angles and the shape of simultaneous pressure distribution are investigated, and the comparisons between numerical results and Goda＇ s predictions are also carried out. It is concluded that the maximum wave forces acting on the unit length of vertical wall is often induced by the obliquely incident waves instead of normally incident waves, while Goda＇ s formula may be inapplicable for oblique wave incidence. The shape of simultaneous pressure distribution is not significantly influenced by incident angles, and it can be favorably predicted by Goda＇ s formula. When regular wave heights are taken as the same as irregular wave height H1%, the irregular wave forces Ph. 1% are slightly larger than regular wave forces in most cases. 相似文献
16.
A mathematical model has been developed to analyze the influence of extreme water waves over multiconnected regions in Visakhapatnam Port, India by considering an average water depth in each multiconnected regions. In addition, partial reflection of incident waves on coastal boundary is also considered. The domain of interest is divided mainly into two regions, i.e., open sea region and harbor region namely as Region-I and Region-II, respectively. Further, Region-II is divided into multiple connected regions. The 2-D boundary element method (BEM) including the Chebyshev point discretization is utilized to solve the Helmholtz equation in each region separately to determine the wave amplification. The numerical convergence is performed to obtain the optimum numerical accuracy and the validation of the current numerical approach is also conducted by comparing the simulation results with existing studies. The four key spots based on the moored ship locations in Visakhapatnam Port are identified to perform the numerical simulation. The wave amplification at these locations is estimated for monochromatic incident waves, considering approximate water depth and different reflection coefficients on the wall of port under the resonance conditions. In addition, wave field analysis inside the Visakhapatnam Port is also conducted to understand resonance conditions. The current numerical model provides an efficient tool to analyze the amplification on any realistic ports or harbors.
相似文献17.
为了研究斜向入射波浪,基于三维不可压缩两相流模型,开发了一套圆形数值波浪水池数值模型。在圆形波浪水池中,通过源项造波法成功生成了任意入射方向的波浪,并且利用人工摩擦项模拟阻尼区以数值耗散反射波浪。模型基于嵌入式多块网格体系,采用FVM法(finite volume method)离散Navier-Stokes方程,VOF法(volume of fluid)追踪自由水面。试验结果表明,斜向入射波浪的模拟结果与理论值基本一致,圆形波浪水池在模拟斜向入射波浪时,有效区域的面积较传统波浪水池显著增大,而且有效区域受波浪入射角度的影响也较小。同时,通过叠加多列斜向入射波浪,模拟出了多向交叉波列,并通过与理论结果对比,发现其具有较高的精度。 相似文献
18.
The purpose of this paper is to extend the validity of Li's parabolic model (1994) by incorporating a combined energy factor in the mild-slope equation and by improving the traditional radiation boundary conditions. With wave breaking and energy dissipation expressed in a direct form in the equation, the proposed model could provide an efficient numerical scheme and accurate predictions of wave transformation across the surf zone. The radiation boundary conditions are iterated in the model without use of approximations. The numerical predictions for wave height distributions across the surf zone are compared with experimental data over typical beach profiles. In addition, tests of waves scattering around a circular pile show that the proposed model could also provide reasonable improvement on the radiation boundary conditions for large incident angles of waves. 相似文献
19.
《Coastal Engineering》2005,52(2):139-149
An improved parabolic water wave transformation model is developed based on generalized [1/1] Padé approximation. For forward scattered waves, the parabolic equation is solved using a marching scheme. The values of wave angles are calculated after the solution of each line; so that better [1/1] generalized Padé approximation is performed. The nonlinear effects are included using a modified dispersion equation. The model is easy to use and performs very well for complex bathymetry. The model is tested for cases of wave angles up to 70°. The numerical results show that for large wave angles, the new parabolic model is better than all the existing parabolic models based on rational approximation. 相似文献
20.
ZHENG Yonghong 《中国海洋工程》2001,(2):185-194
The original hyperbolic mild-slope equation can effectively take into account the combined effects of wave shoaling, refraction, diffraction and reflection, but does not consider the nonlinear effect of waves, and the existing numerical schemes for it show some deficiencies. Based on the original hyperbolic mild-slope equation, a nonlinear dispersion relation is introduced in present paper to effectively take the nonlinear effect of waves into account and a new numerical scheme is proposed. The weakly nonlinear dispersion relation and the improved numerical scheme are applied to the simulation of wave transformation over an elliptic shoal. Numerical tests show that the improvement of the numerical scheme makes efficient the solution to the hyperbolic mild-slope equation. A comparison of numerical results with experimental data indicates that the results obtained by use of the new scheme are satisfactory. 相似文献