Least Square Finite Element Method for Viscous Splitting of Unsteady Incompressible Navier–Stokes Equations

In order to solve unsteady incompressible Navier–Stokes(N–S) equations, a new stabilized finite element method,called the viscous-splitting least square FEM, is proposed. In the model, the N–S equations are split into diffusive and convective parts in each time step. The diffusive part is discretized by the backward difference method in time and discretized by the standard Galerkin method in space. The convective part is a first-order nonlinear equation.After the linearization of the nonlinear part by Newton's method, the convective part is also discretized by the backward difference method in time and discretized by least square scheme in space. C~0-type element can be used for interpolation of the velocity and pressure in the present model. Driven cavity flow and flow past a circular cylinder are conducted to validate the present model. Numerical results agree with previous numerical results, and the model has high accuracy and can be used to simulate problems with complex geometry.     

台风移动规律的研究 Ⅱ．小地形与边界层的动力作用

从支配台风中心移动的基本方程出发，着重分析了小地形（地形高度与台风系统的垂直厚度相比为小量）的抬升作用和边界层的摩擦作用对台风移动影响的定性特征。结果表明，较高地势对台风有“吸引”作用；边界层摩擦辐合引起的艾克曼抽吸有利于台风产生沿局地流场引导速度方向的加速度。     

First six months quality assessment of HY-2A SCAT wind products using in situ measurements

The first Chinese microwave ocean environment satellite HY-2A, carrying a Ku-band scatteromenter （SCAT）, was successfully launched in August 2011. The first quality assessment of HY-2A SCAT wind products is presented through the comparison of the first 6 months operationally released SCAT products with in situ data. The in situ winds from the National Data Buoy Center （NDBC） buoys, R/V Polarstern, Aurora Australis, Roger Revelle and PY30-1 oil platform, were converted to the 10 m equivalent neutral winds. The temporal and spatial differences between the HY-2A SCAT and the in situ observations were limited to less than 5 min and 12.5 km. For HY-2A SCAT wind speed products, the comparison and analysis using the NDBC buoys yield a bias of-0.49 m/s, a root mean square error （RMSE） of 1.3 m/s and an increase negative bias with increasing wind speed observation above 3 m/s. Although less accurate of HY-2A SCAT wind direction at low winds, the RMSE of 19.19° with a bias of 0.92° is found for wind speeds higher than 3 m/s. These results are found consistent with those from R/Vs and oil platform comparisons. Moreover, the NDBC buoy comparison results also suggest that the accuracy of HY-2A SCAT winds is consistent over the first half year of 2012. The encouraging assessment results over the first 6 months show that wind products from HY-2A SCAT will be useful for scientific community.     

基于皮肤转录组的半滑舌鳎无眼侧黑化相关基因的筛选鉴定

半滑舌鳎(Cynoglossus semilaevis)作为比目鱼(Pleuronectiformes)中的代表物种,是我国沿海地区重要的海水经济鱼类.半滑舌鳎体色异常的问题长期以来一直困扰着从业者.导致体色变化的原因多种多样,遗传因素是最根本原因.针对半滑舌鳎无眼侧黑化的研究多在环境、营养、生理、常见色素基因克隆等方...     

Fluid—Structure Interaction of Two-Phase Flow Passing Through 90° Pipe Bend Under Slug Pattern Conditions

China Ocean Engineering - Numerical simulations of evolution characteristics of slug flow across a 90° pipe bend have been carried out to study the fluid—structure interaction response...     

A Lagrangian study of the near-surface intrusion of Pacific water into the South China Sea

Satellite-tracked Lagrangian drifters are used to investigate the transport pathways of near-surface water around the Luzon Strait. Particular attention is paid to the intrusion of Pacific water into the South China Sea(SCS).Results from drifter observations suggest that except for the Kuroshio water, other Pacific water that carried by zonal jets, Ekman currents or eddies, can also intrude into the SCS. Motivated by this origin problem of the intrusion water, numerous simulated trajectories are constructed by altimeter-based velocities. Quantitative estimates from simulated trajectories suggest that the contribution of other Pacific water to the total intrusion flux in the Luzon Strait is approximately 13% on average, much smaller than that of Kuroshio water. Even so, over multiple years and many individual intrusion events, the contribution from other Pacific water is quite considerable. The interannual signal in the intrusion flux of these Pacific water might be closely related to variations in a wintertime westward current and eddy activities east of the Luzon Strait. We also found that Ekman drift could significantly contribute to the intrusion of Pacific water and could affect the spreading of intrusion water in the SCS. A case study of an eddy-related intrusion is presented to show the detailed processes of the intrusion of Pacific water and the eddy-Kuroshio interaction.     

Application of High Energy Dynamic Compaction in Coastal Reclamation Areas

High energy dynamic compaction (HEDC) is adopted in a coastal reclamation area because the grain size of backfilled soil mostly ranges between 20 cm and 100 cm. The in situ tests for evaluating the effectiveness of HEDC were performed on the backfilled soil ground. The crater depth per drop and the whole test zone elevations before and after HEDC were measured and analyzed. Dynamic penetration tests and spectral analysis of surface wave (SASW) tests were used for investigating the improvement depth. Furthermore, the allowable bearing capacity of HEDC treated ground was determined based on the results of plate-load tests. It was found that HEDC did not cause the ground surface heave during construction, and was more effective than low energy dynamic compaction (LEDC) in terms of applied energy utilization. Based on the test results, the improvement depth of HEDC at this site was not less than 14 m, and there was no obvious weak layer within the range of improvement depth. The allowable bearing capacities were larger than 160 kPa. The investigation results indicate that the HEDC technique is an effective way for improving backfilled coarse-grained soil in coastal reclamation areas. This technique helps to achieve both greater improvement depths and higher ground bearing capacities as compared with LEDC.     

台湾以北海域浮游桡足类生物海洋学特征的研究Ⅱ.群落特征

在对台湾以北海域浮游桡足类生物海洋学特征进行数量分布方面的研究后的续篇,重点对本海区浮游挠足类的群落结构和群落性质以及与栖区环境条件间的关系作了分析探讨．结果表明,本区桡足类群落结构种类组成复杂,出现种类共２３７种,但周年共有种比例仅占３２％．桡足类群落的多样度和均匀度年均值各为３．７１４和０．６９０,在平面分布上呈外部海区高于近岸海区的大体趋势．本区群落可划分为５个生态类群,其中暖水性外海高温偏低盐类群和热带大洋高温高盐类群可分别指示台湾海峡水和黑潮表层水的季节消长过程．从不同侧面的计算分析均表明,冬季在环境条件上均有异于其他３季．在春、夏、秋季,以普通波水蚤最具优势,盐度是影响群落特征值的主导因子,群落的性质是以暖水性外海种类为主、热带大洋种也占相当比例的亚热带－热带群落结构的特点;在冬季,主要优势种是海洋真刺水蚤,温度是群落特征值的主要制约因子,群落呈现以热带大洋种占支配地位的热带大洋群落结构属性．     

山东栖霞桃村地区中酸性火山-侵入杂岩岩石地球化学及其成因研究

山东栖霞桃村地区出露中生代中酸性火山-侵入杂岩,对采自桃村地区青山组下段的中酸性火山-侵入岩以进行了岩石学和地球化学研究。桃村地区的中酸性火成岩的地球化学特征为:高钾低钠,高铝低镁;Cr,Co,Ni含量较低,Sr/Y及(La/Yb)N比值很高;微量元素蛛网图显示富集不相容元素K,Rb,Ba和Th,以及不相容元素Ce,Hf和Ti,亏损高场强元素Ta,Nb以及P;轻重稀土元素分馏程度高,具有类似埃达克岩的性质。综合分析其地球化学特征显示,青山组下段中酸性杂岩为增厚的下地壳熔融,这种地壳的增厚作用可能由古太平洋板块俯冲作用引起,而在俯冲作用过程中青山组中酸性杂岩的源岩被俯冲沉积物混染。     

成山头海域潮流能资源可开发量评估

针对潮流能资源较丰富的成山头外海域,利用FVCOM数值模式,在良好模拟该海域潮流场的基础上,运用能量耗散原理,对该海域的潮流能资源可开发量进行了评估。结果表明,在转换装置的拖拽系数为0.07时,面积为27km2的成山头近岸海域的可开发潮流能资源约为17.9MW,其中大潮期间的可开发量高达37.7MW,而小潮期间则为7.3MW。在此条件下,该海域大潮期间涨急和落急时刻的流速分别减小了40%和38%,但发电装置对潮汐的影响较小,在成山头顶端的高潮潮位仅下降了4cm。