潮流与泥沙数值模拟回顾及进展

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。     

江苏如东西太阳沙及烂沙洋海域潮流泥沙数值模拟

基于不规则三角形网格有限差分法并考虑波浪及其破碎作用,建立了平面二维潮流场和泥沙场数学模型.该模型对有望建设成深水码头和深水航道的江苏如东西太阳沙和烂沙洋海域的潮流场和泥沙场进行了细化数值模拟.数值模拟结果表明：（1）本海区潮流基本上是顺深槽流动的往复流,潮流流速大,烂沙洋北水道和西太阳沙附近大潮涨落潮最大流速分别在2 m/s和1 m/s以上;（2）本海区的潮平均水体含沙量在0.5 kg/m^3以下,落潮含沙量大于涨潮含沙量;（3）小浪对水体含沙量影响很小,大浪作用下水体含沙量明显增加.     

葫芦岛港柳条沟港区规划潮流泥沙数模研究

建立了基于不规则三角形网格的考虑波浪作用的潮流泥沙数学模型,在对模型进行充分验证的基础上,对葫芦岛海域的潮流、泥沙场的进行了数值模拟,对该海区的潮流扬、泥沙场特征进行了分析;对萌芦岛港柳条沟港区规划方案进行了潮流、泥沙场模拟研究。详细分析了工程前后港池和航道的流扬变化,计算了航道的横流,预报了规划港区港池和航道的泥沙年淤积量,为港区的规划设计提供了科学依据。     

电厂港池取水工程泥沙回淤研究

运用半封闭港区水域泥沙回淤研究结果，以及电厂港池取水物理模型试验结果，提出电厂港池取水回淤计算模式。应用此模式对某港拟建电厂各取水工况进行港池航道回淤计算分析。     

石臼港潮流数值模拟试验

计算方法如图(3)所示,石臼港面临广阔的海域,曲线表示岸线,A、B、C、D为岸线格网点。二期工程拟从A点至E点修建码头和防波堤。建成后港内X方向最大距离为5100米,Y方向在湾口处为2600米。三期工程如图(5)所示,湾口宽为500米。二、三期工程建成后,港内的潮流流场必将发生巨大的变化。建港前预知建港后的潮流     

大鹏湾潮流场的数值模拟

本文根据描述潮流运动变化的连续方程和运动方程,用ADI方法建立差分方程,对大鹏湾潮流场进行了数值模拟;从而根据数值模拟结果和实测结果,对大鹏湾的潮流和潮汐余流等进行了讨论。     

海南南山外海潮流的数值模拟

本文建立了三个不同大小和不同分辨率的数值模型,得到了海南南山外海高分辨率的计算結果,与实测结果符合良好。     

长江口南支潮流的一个数值模拟

为了能够精确地拟合天然水域不规则的水陆边界,并能保持有限差分数值计算在矩形网格中进行,本文利用Thompson的数值网格生成技术,在长江口南支七丫口至横沙河段设计了一个椭圆型边界拟合坐标系,并在这个坐标系下建立了平面二维潮流数学模型。通过数值求解此数学模型,实现了计算区域内现状潮流的一个数值模拟,模拟结果表明,模式的设计是成功的。     

厦门嵩屿电厂取水区域泥沙问题分析

本文在现场实测资料及模型试验成果基础上,针对嵩屿电厂三期工程具体特点,分析了九龙江河主取水口水域的自然条件和河床冲淤变化计算了取水口附近泥沙回淤量,并对取水口区域岸稳定性作了分析。结果表明,嵩屿电厂三期取水口建成后,其附近泥沙回淤强度为２５－２７ｃｍ／ａ。     

北部湾潮汐潮流的数值模拟

基于正交曲线坐标的ECOMSED三维水动力模式,对北部湾的潮汐潮流进行数值模拟。选用不同的海底摩擦系数、海底粗糙度系数以及水平湍流摩擦系数进行数值试验。试验结果表明,当海底摩擦系数取2×10-3～3×10-3,海底粗糙度系数取1×10-3～2×10-3m,而水平湍流摩擦系数取1×102～5×103m2/s时,模拟所得潮汐、潮流结果与实测数据吻合较好;并由此对北部湾的潮汐、潮流和潮余流等特征进行了分析。还给出了垂直湍流黏滞系数呈抛物型的分布特征。对该海域的水动力状况有了进一步的了解,为该海域的环境保护规划提供了科学依据。     

Numerical Tidal Current Modeling Using Fine Boundary Fitted Grids for Tidal Flats

Fine grids with small spacing in boundary-fitted coordinates are normally used to treat thecomputation of fluid dynamics for estuarine areas and tidal flats.However,the adoption of Cartesian com-ponents of velocity vectors in this kind of non-orthogonal coordinates will definitely result in a diffculty insolving implicitly the transformed momentum equations,and also complicate the wet-dry point judgementused for flood areas.To solve this problem,equations in terms of generalized contravariant velocityvectors in curvilinear coordinates are derived in the present study,by virtue of which,anAlternative-Direction-Implicit numerical scheme in non-orthogonal grids would then be easily obtained,and wet-dry point judgement would as well be largely simplified.A comparison is made between the explic-it scheme and implicit scheme,showing that the present model is accurate and numerically stable for com-putations of fluid dynamics for estuarine areas and tidal flats.     

瓯江口外洞头岛北岙后涂围垦工程潮流数值模拟研究

通过建立基于不规则三角形差分法的洞头岛附近海区二维潮流数学模型,在对现场实测资料验证的基础上,对北岙后涂围垦工程前后的潮流场进行了数值模拟,就北岙后涂围垦工程对周边海区的影响及围塘根部的冲刷情况进行了分析研究。分析研究结果表明,围垦工程不会对客运和货运码头及航道通航条件产生明显影响,对洞头峡的涨落潮水流、三盘大桥桥墩及其通航孔基本没有影响;单纯潮流对围塘根部冲刷的可能性很小,因此,围垦工程是可行的。     

广西近岸海域潮流数值模拟

采用有限元三角形网格的分步杂交方法,建立了广西近岸海域的二维潮流数值模型,计算值与实测资料符合较好。采用主要分潮组合输入,模拟了研究海域的平均潮潮流场。模拟结果表明:涨急时,潮流向为东北方向,最大涨潮流速为74cm/s左右;落急时,潮流向为西南方向,最大落潮流速约100cm/s,落潮流速大于涨潮流速。近岸区域潮流为往复流,离岸边越远潮流越接近旋转流。     

Corrected Formula of Bed Resistance Coefficient for Plane Numerical Simulation of Tidal Current

By means of a logarithm law for the velocity profile,a corrected formula of bed resistancecoefficient,which involves many factors such as gradient of still water depth,variation of surfaceelevation,flow direction,and so on,is derived from the 3D governing equations of tidal current by aver-aging over the whole water depth.Theoretical analysis and application have shown that the 2D plane tidalcurrent numerical model would be more reasonable and could be applied to steep bottom topographywhen the corrected bed resistance coefficient is used,therefore the results of reproduction simulation andengineering calculation would be more scientific and reasonable.     

胶州湾潮汐潮流高分辨率数值模拟研究

基于采用无结构网格和有限体积方法的FVCOM陆架模式,考虑8个主要的天文分潮,建立胶州湾三维高分辨率数值模型来重现和研究其潮汐潮流变化状况。与实测资料对比验证表明,模拟结果与实测值吻合较好。在此基础上,根据模拟结果计算得到了较以往更为精细的同潮图和潮汐、潮流、余流分布特征。研究结果揭示,最大可能潮流和最大余流都发生在团岛附近,流速分别可达2.14和0.43 m/s;除了湾口附近前人报道过的4个余流系统外,还在中部首次揭示了2个相对较弱的余流系统;潮流能通量在内外湾口呈"左进右出"的结构;胶州湾的平均纳潮量为8.31亿m3;染色试验表明,胶州湾30 d的水交换率为36.8%。     

Two-Dimensional Mathematical Model of Tidal Current and Sediment for Oujiang Estnary and Wenzhou Bay

A 2-D mathematical model of tidal current and sediment has been developed for the Oujiang Estuary and the WenzhouBay. This model accomodates complicated features including multiple islands, existence of turbidity, and significant differ-ence in size distribution of bed material. The governing equations for non-uniform suspended load and bed load transport arepresented in a boundary-fitted orthogonal curvilinear coordinate system. The numerical solution procedures along with theirinitial conditions, boundary conditions, and movable boundary technique are presented. Strategies for computation of thecritical condition of deposition or erosion, sediment transport capacity, non-uniform bed load discharge, etc. are suggested.The model verification computation shows that, the tidal levels computed from the model are in good agreement with the fielddata at the 18 tidal gauge stations. The computed velocities and flow directions also agree well with the values measuredalong the totally 52 synchronously observed verticals distributed over 8 cross sections. The computed tidal water throughputsthrough the Huangda‘ao cross section are close to the measured data. And the computed values of bed deformation fromYangfushan to the estuary outfall and in the outer-sea area are in good agreement with the data observed from 1986 to 1992.The changes of tidal volumes through the estuary, velocities in different channels and the bed form due to the influence of thereclamation project on the Wenzhou shoal are predicted by means of this model.     

胶州湾海域潮流动力特征及其与含沙量的关系

根据2009年胶州湾海域的悬沙、流速、流向的实测资料,应用短期资料的潮流准调和分析方法,对连续海流资料进行了分析,并结合悬沙资料,对含沙量与潮流之间动力关系进行了探讨。研究结果表明:该海域潮流属于正规半日潮流性质,半日分潮流的东分量大于北分量,潮流以带有旋转性质的往复流为主,涨潮流流向偏西,落潮流流向偏东。胶州湾内含沙量分布特征与海底沉积物粒径特征基本一致。含沙量在涨落潮的交替和流速的更迭作用下出现明显的周期性变化,含沙量的峰值基本与海域半日潮流特点相对应,几乎每1个流速峰值对应1个含沙量的峰值,含沙量的峰值一般出现在流速峰值之后。胶州湾口处流速和单宽输沙量都为最大,涨潮单宽输沙量大于落潮单宽输沙量,输沙方向为偏西向。