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1.
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   

2.
基于一种高阶Boussiensq方程(刘忠波等,2004),采用预报-校正格式的有限差分法对该方程进行了数值离散,建立了数值模型。针对动量方程中三阶项的差分形式,采用了迎风格式和五点格式。通过数值模拟常水深下不同周期波浪传播变形,指出迎风格式在计算小周期波浪时存在的问题。为进一步验证数值模型的适用性,模拟了淹没潜堤上的传播变形。从数值结果与实验值的对比结果上看,该数值模型能较好地模拟波浪变形,可用于模拟实际中的波浪场问题。  相似文献   

3.
砂质海岸突堤式建筑物下游岸线变形数学模型   总被引:2,自引:1,他引:2  
提出了一种改进的砂质海岸岸滩演变的“一线理论”数学模型.该模型中考虑了岸滩演变过程中岸滩坡度变化的影响,并采用波浪折射、绕射和反射联合计算数学模型模拟掩护区的波浪场,提高了波浪计算的精度.实例计算表明,在验证资料比较充分的条件下,该数学模型计算结果的可靠度较高,可供实际工程规划和设计时参考使用.  相似文献   

4.
A reformed numerical model based on the “one-line theory” for beach deformation is presented. In this model, the change of beach slope during coastline procession is considered.A wave numerical model combined with wave refraction, diffraction and reflection is used to simulate wave climate to increase numerical accuracy.The results show that the numerical model has a good precision based on the adequate field data. The results can be applied to practical engineering.  相似文献   

5.
This paper aims at investigation of the dynamic properties of gravity cage exposed to waves by use of a numerical model. The numerical model is developed, based on lumped mass method to set up the equations of motion of the whole cage; meanwhile the solutions of equations are solved by the Runge-Kutta-Verner fifth-order and sixth-order method. Physical model tests have been carried out to examine the validity of the numerical model. The results by the numerical simulation agree well with the experimental data.  相似文献   

6.
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  
唐军  李巧生  沈永明 《海洋学报》2013,35(5):162-168
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   

7.
基于推板造波理论和摇板造波理论,在Open FOAM平台上采用重叠网格技术建立黏性数值波浪水槽,并使用一种结合SIMPLE算法和PISO算法的PIMPLE算法对数值模型进行求解。利用开发的数值模型通过数值收敛性测试和网格独立性测试分别重点研究了时间步长、库朗数和网格尺寸对数值精度和计算效率的影响。并对比研究了此数值模型分别嵌入层流模型和湍流模型的计算精度和计算效率。实现的规则波和二阶有限振幅波与理论结果和试验结果吻合,验证了此黏性数值波浪水槽的造波和主动消波功能。基于二维数值波浪水槽,进一步研究了三维数值造波,数值计算结果与理论结果吻合良好。研究结果不仅验证了重叠网格在二维和三维两相流体域中求解运动物体与流场交互的可靠性和正确性,而且为使用此黏性数值波浪水槽解决更复杂的海洋工程问题提供了依据。  相似文献   

8.
唐蔚  孙大鹏  吴浩 《海洋工程》2017,35(4):44-52
采用三步有限元法对N-S方程进行离散,同时借助CLEAR-VOF方法追踪流体自由表面,利用主动吸收式造波等手段改进了二维不规则波浪数值水槽,使得水槽中的波浪谱与目标靶谱吻合较好。进而建立了不规则波浪与开孔沉箱作用一种新的数值模式,分析研究不规则波作用下开孔沉箱的反射率,并与现有的物模结果和数模结果进行了对比,为不规则波与开孔沉箱作用问题的研究,探求了一种新的数值手段。  相似文献   

9.
A numerical model for wave propagation in a harbour is verified by use of physical models.The extended time-dependent mild slope equation is employed as the governing equation,and the model is solved by use of ADI method containing the relaxation factor.Firstly,the reflection coefficient of waves in front of rubble-mound breakwaters under oblique incident waves is determined through physical model tests,and it is regarded as the basis for simulating partial reflection boundaries of the numerical model.Then model tests on refraction,diffraction and reflection of waves in a harbour are performed to measure wave height distribution.Comparative results between physical and numerical model tests show that the present numerical model can satisfactorily simulate the propagation of regular and irregular waves in a harbour with complex topography and boundary conditions.  相似文献   

10.
张洪生  冯文静  商辉 《海洋学报》2007,29(5):161-173
以一种新型的含变换速度变量的Boussinesq型方程为控制方程组,采用五阶Runge-Kutta-England格式离散时间积分,采用七点差分格式离散空间导数,并采用恰当的出流边界条件,从而建立了非线性波传播的新型数值模拟模型.对均匀水深水域内波浪传播的数值模拟,说明在引入变换速度后进一步增大了模型的水深适用范围.对潜堤地形上波浪传播的数值模拟说明,在引入变换速度后进一步提高了模型的数值模拟精度.  相似文献   

11.
本文建立一个温带风暴潮模式,包括海上边界层风场模式和风暴潮数值模式。利用建立的温带风暴潮模式,模拟了影响连云港的几次显著温带风暴潮过程,结果表明,本模式所采用的海上边界层风场模式和风暴潮数值模式是匹配的,能够满足海洋工程中的风暴潮数值计算的需要,甚至可以成为日常温带风暴潮数值预报的有用手段。  相似文献   

12.
潮流与泥沙数值模拟回顾及进展   总被引:9,自引:0,他引:9  
回顾和总结了近年来国内外潮流与泥沙数值模拟的进展,评价分析了数学模型的多种数值解法,特别是有关二维、三维潮流数值模拟以及水沙数学模型近年来的进展,并根据目前潮流、泥沙数值模拟技术中存在的不足,讨论了进一步研究的方向和发展趋势。  相似文献   

13.
This paper focuses on the numerical modelling of tsunami propagation in the open Black Sea. Two types of numerical models are discussed: a model for the radial propagation of long waves and an evolutionary finite-difference prognostic model. Experimentally derived numerical data on the model source of tsunamis are reported. Translated by Vladimir A. Puchkin.  相似文献   

14.
Studyonshort-rangenumericalforecastingofoceancurrentintheEastChinaSea-ⅢThree-dimensionalbaroclinicanomalyforecastingmodelandi...  相似文献   

15.
In an attempt to contribute to efforts for a robust and effective numerical tool addressing ship motion in astern seas, this paper presents the development of a coupled non-linear 6-DOF model with frequency dependent coefficients, incorporating memory effects and random waves. A new axes system that allows straightforward combination between seakeeping and manoeuvring, whilst accounting for extreme motions, is proposed. Validation of the numerical model with the results of benchmark tests commissioned by ITTC's Specialist Group on Stability demonstrated qualitative, yet not fully satisfactory agreement between numerical and experimental results in line with other predictive tools. The numerical results indicate that the inclusion of frequency coefficients definitely affects the accuracy of the predictions. In order to enhance further the numerical model and obtain useful information on motion coupling, extensive captive and free running model tests were carried out. Good agreement with the experimental results was achieved. These studies provide convincing evidence of the capability of the developed numerical model to predict the dangerous conditions that a ship could encounter in extreme astern seas. As a result, it could offer new insights towards establishing relationships linking ship behaviour to design, environmental and operational parameters.  相似文献   

16.
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   

17.
非线性波传播的新型数值模拟模型及其实验验证   总被引:3,自引:4,他引:3  
以一种新型的Boussinesq型方程为控制方程组,采用五阶Runge-Kutta-England格式离散时间积分,采用七点差分格式离散空间导数,并通过采用恰当的出流边界条件,从而建立了非线性波传播的新型数值模拟模型.通过对均匀水深水域内波浪传播的数值模拟说明,模型能较好地模拟大水深水域和强非线性波的传播.通过设置不同的入射波参数来进行潜堤地形上波浪传播的物理模型实验,并将数值解与物理模型实验结果进行了比较.  相似文献   

18.
LAGFD-WAM海浪数值模式是一种第三代海浪数值模式,通过求解波数谱平衡方程,并考虑风输入、波浪破碎耗散、底摩擦耗散、波波非线性相互作用和波流相互作用等源函数,模拟波数空间下的海浪方向谱,并依此获得海浪的波高、周期和平均波向。该模式的一个显著特点是采用特征线嵌入格式求解海浪的传播。在进行浅水区域的海浪模拟时,特征线嵌入格式的数值计算方案是否合理对海浪数值模拟结果产生直接的影响。为此LAGFD-WAM海浪数值模式提出了一种新的特征线混合数值计算格式,并应用于浅水海浪数值模拟。结果表明,采用该计算方法,能够使数值模拟结果与实测结果很好符合。  相似文献   

19.
《Coastal Engineering》2006,53(10):845-855
This paper presents a study of wave damping over porous seabeds by using a two-dimensional numerical model. In this model, the flow outside of porous media is described by the Reynolds Averaged Navier–Stokes equations. The spatially averaged Navier–Stokes equations, in which the presence of porous media is considered by including additional inertia and nonlinear friction forces, is derived and implemented for the porous flow. Unlike the earlier models, the present model explicitly represents the flow resistance dependency on Reynolds number in order to cover wider ranges of porous flows. The numerical model is validated against available theories and experimental data. The comparison between the numerical results and the theoretical results indicates that the omission or linearization of the nonlinear resistance terms in porous flow models, which is the common practice in most of analytical models, can lead to significant errors in estimating wave damping rate. The present numerical model is used to simulate nonlinear wave interaction with porous seabeds and it is found that the numerical results compare well with the experimental data for different wave nonlinearity. The additional numerical tests are also conducted to study the effects of wavelength, seabed thickness and Reynolds number on wave damping.  相似文献   

20.
1IntroductionThe fish farming and aquaculture industry areexpanding and the demand for suitable locations forfish farms is increasing.In the future,more of thefish farms will be located offshore,as the number ofsuitable nearshore locations is limited.Futu…  相似文献   

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