印尼某滨海电厂工程取排水口布置

为了减小滨海电厂温排水对取水以及周围环境的影响,采用非结构化网格,建立平面二维水动力模型,经率定和验证后对印尼西加里曼丹燃煤电厂不同取排水平面布置方案下的温排水扩散进行了数值模拟。研究结果表明,排水口位置及隔热堤长度、走向对温排水影响较大;应尽量增大取排水口之间的水平或垂向扩散距离;取排水布置还应考虑对周围海域生态环保的影响。文章根据研究结果与分析给出了取排水平面布置推荐方案,为取排水工程的设计提供了科学依据。     

南海台风特征及台风场数值改进研究

通过搜集南海台风资料,对近10 a南海台风的规律进行了总结。利用Ueno台风风场模型和改进的藤田公式,引入压差修正系数和后报风场数据,构建了1330和1409号台风风场,并应用测站观测资料对模拟数据进行对比与误差分析。结果表明:西北太平洋移入南海的热带气旋整体上比南海生成的热带气旋数量多、强度大;南海海域生成的登陆台风在我国登陆较少,多在越南登陆。改进的模型风场极值相对误差小;引入后报数据后,合成风场数据相关性更好,误差更小。     

通州湾区域用海对近岸波浪场的影响

采用CCMP背景风场与Holland梯度风场模型叠加构建新的SWAN驱动风场,对台风"梅花"期间东中国海的波浪场进行数值模拟,并结合卫星数据进行验证,讨论了拖曳力系数饱和值的最适选取,以给小范围提供最佳波谱边界。运用SWAN自嵌套进行小范围数值模拟研究,结合波浪测站实测数据进行对比,对区域用海后保留通道的两种方案进行对比分析。结果表明,台风期间保留西通道较东通道有效波高更小,所取特征站位平均减幅0.10m,最大降幅达0.25m。     

双台风下江苏沿海的波浪数值模拟

为研究江苏沿海海域受双台风布拉万和天秤的影响情况,应用Holland模型与ERA背景风场数据构建双台风布拉万和天秤的模拟风场,结合MIKE SW模块进行台风浪的数值模拟试验,通过与卫星轨道数据、实测站点数据对比对模拟的有效波高进行了验证,研究了东中国海范围和江苏沿海海域的波浪场(混合浪、风浪和涌浪)特征。其中,在模拟风场的构建中,比例系数e至为关键,通过进行参数试验确定较优系数值。研究结果表明台风布拉万主要以风浪形式影响江苏沿海海域,出现的风浪最大值为10.4 m,台风天秤是以涌浪形式影响,涌浪最大值为2.4 m,且台风布拉万的影响强度明显大于台风天秤。     

基于SWAN模式对台风海燕风浪的推算

选用内域藤田外域高桥的混合风场模拟台风风场,应用第三代海浪数值模式SWAN对2013年影响南海海域的超级台风＂海燕＂进行台风浪的推算。通过对测点处风速以及推算出有效波高与实测数据对比,分析发现模式计算结果与实测吻合良好。同时将其应用到南海海域波浪场的推算,能够很好地刻画台风经过时波浪场在时间和空间的变化,可为以后风浪的预报提供参考。     

两种海浪模式模拟结果的对比研究

利用合成风场驱动SWAN和WAVEWATCHⅢ这两种海浪模式,分别模拟了墨西哥湾海域和印度洋海域的海浪,并将两种海浪模式的模拟结果与波浪实测资料及Jason-1卫星高度计观测资料进行对比研究。研究结果表明:以CCMP风场为背景风场,合成Myers台风模型风场所得的合成风场能较好地模拟台风风场,但对于部分台风风场,模拟结果明显偏小。WW3对台风浪的模拟效果偏弱,SWAN模拟效果更好,与实测值更接近;对于大范围海域的海浪模拟,SWAN对涌浪传播的模拟耗散较大,模拟的波高和周期均偏小,而WW3模拟效果更好。     

不同风场模式下“灿鸿”台风浪数值模拟及应用

分别采用3种不同的梯度风场模型与欧洲中尺度背景风场叠加构建新的海面驱动风场,基于非结构化网格,利用SWAN模式对北上型台风"灿鸿"进行数值模拟,并结合卫星数据进行对比论证,得出捷式合成风场最佳,Holland次之,藤田最差。采用捷式合成风场进行模拟计算以给小范围提供最佳边界谱,利用SWAN自嵌套模式对小范围进行数值模拟计算分析,通过波浪测站的浮标数据进行验证,吻合度较高。对南通近海近、远期区域建设用海规划工程的实施进行波高对比分析发现:相较近期,远期规划工程实施后,南部航道水域平均有效波高增幅更大;而东部区域平均波高降幅更明显。     

Ashdod港风浪特性研究

利用欧洲中期天气预报中心ECMWF近38 a(1979~2016年)逐6 h的ERA-Interim全球再分析资料与该港区3 a实测数据同化后的有效波高、平均周期、平均波向和海表10 m风场资料,对Ashdod港工程区风、浪特征进行了统计分析,得出该海区常浪向和常风向均为WNW向,强浪向为WNW,强风向为ESE向,进而分析了有效波高和周期的联合分布,得出有效波高1 m,周期5 s的波浪出现概率最大。通过有效波高和风速、平均波向和风向数据的相关性分析,结果表明:冬季风浪为主导,春、夏、秋三季均是涌浪为主导。不同方向不同重现期的波要素统计分析,可为Ashdod港口建设提供科学依据,研究方法也可为类似工程借鉴。     

潍坊港海域波浪数值模拟*

采用WRF风场模式和SWAN海浪模式,分别进行渤海湾的风场和波浪场后报计算,并以波浪气象浮标实测数据对风场和波浪场进行验证,效果良好。以后报结果为样本,采用P-Ⅲ型拟合方法,对莱州湾湾口-15 m等深线处的风场与波浪进行统计分析,得到50 a一遇的设计要素值。运行MIKE21 SW模块建立潍坊港海域的波浪数值模型,进行50 a一遇重现期下的波浪浅水传播计算。模拟结果表明,该模型适用于模拟潍坊港附近海域的波浪传播过程,计算结果可为港区的码头、沙堤和航道等的设计和建设提供参考     

台风浪数值模拟中风场权重系数分析

文章采用藤田气压模型与背景风场构造的合成风场,驱动SWAN波浪模型,模拟不同权重系数下经过东中国海海域的6个北上行台风,在对比分析模拟结果之后,提出了权重系数的改进措施,有效的优化了风场的构造方式以及波浪场的模拟精度。     

SWAN风浪成长模型在近海设计波浪要素推算中的应用

根据黄、渤海区20 a中最大风速对应的风场过程,利用SWAN模型模拟风浪的成长过程,利用针对模型推算所得的烟台芝罘岛附近海域的系列波浪要素,进行P-III型曲线的拟合分析,得到不同重现期条件下的特征波浪要素。模型计算过程中,只需对美国NCEP和欧洲ECMWF风场后报资料进行简单校正,据此通过SWAN模型推算的特征波浪要素值就可与根据芝罘岛海洋环境监测站现场观测资料推断的波浪要素值基本一致。     

Assessment of wind quality for oceanographic modelling in semi-enclosed basins

The quality of surface winds derived from four meteorological models is assessed in the semi-enclosed Adriatic Sea over a 2-month period: a global hydrostatic model ECMWF T511 (40 km resolution), a hydrostatic limited area model LAMBO (20 km), and two non-hydrostatic limited area models: LAMI (7 km) and COAMPS™ (4 km). These wind models are used to drive a 2 km resolution wave model (SWAN) of the Adriatic, and wind and wave results are compared with observations at the ISMAR oceanographic tower off Venice. Waves are also compared at buoy locations near Ancona and Ortona. Consistently with earlier studies, the ECMWF fields underestimate the wind magnitude and do not reproduce the known spatial structure of strong wind events. The results show that the higher-resolution, limited area models LAMI and COAMPS exhibit better amplitude response than the coarser ECMWF: there is a 3- to 4-fold reduction of the wind underestimation at the platform (from 36% to 8–11%). The wave response is also improved with LAMI and COAMPS: there is a 2-fold reduction in the underestimation of wave heights at the platform. These non-hydrostatic models also produce wind fields with more realistic small-scale, spatial structure during strong wind events. The temporal correlation between observed and modelled wind, however, is highest with the global ECMWF model due to the fact that large-scale features can be predicted deterministically, whereas small-scale features can only be predicted stochastically. Models with less small-scale structure have better correlation because they have less “noise.” This explanation is supported by increased correlation between modelled and observed waves, the waves representing a smoothing of the wind over fetch and duration. Although there is room for improvement, the high-resolution, non-hydrostatic models (LAMI and COAMPS) offer significant advantages for driving oceanographic simulations in semi-enclosed basins such as the Adriatic Sea.     

Variability of the Bohai Sea circulation based on model calculations

The circulation and the hydrography of the Bohai Sea are simulated with the Hamburg Shelf Ocean Model (HAMSOM). The model is three-dimensional, prognostic baroclinic and has a resolution of 5 min in latitude and longitude and 10 layers in the vertical. It is initialised and forced with the five main tidal constituents, temperature and salinity distributions taken from the Levitus database, monthly mean river run-off values and European Centre for Medium Range Weather Forecast (ECMWF) re-analysed data of air pressure, wind stress and of those parameters relevant for the calculation of heat fluxes. The simulation period covers 14 years from 1980 to 1993 due to the availability of the time-dependent ECMWF forcing.The results are analysed by means of time series and EOFs focussing on the interpretation of fluctuations with periods above the tidal cycle. Furthermore, tracer simulations are carried out and turnover times are calculated in order to evaluate the importance of these fluctuations on the renewal and transport of water masses in the Bohai Sea.One of the major outcomes of the investigation is the overall dominance of the annual cycle in all hydrographic parameters and the importance of stochastic weather fluctuations on the transport of water masses in the Bohai Sea.     

Operational Oceanography System applied to the Prestige oil-spillage event

This contribution describes the procedure used during the Prestige oil-spillage event, by means of an Operational Oceanography System, and the behaviour of the present prediction tools (hydrodynamic and dispersion models) applied to it. The accuracy of these tools is estimated by a reanalysis of field data transmitted by a sea surface drifting buoy, released at the time of the oil spill. The numerical models applied were the Regional Ocean Modeling System (ROMS), fed by the available six-hourly NCEP atmospheric information, together with a Lagrangian Particle-Tracking Model (LPTM). ROMS has been used to estimate the current fields for the Bay of Biscay, whilst the LPTM has provided the oil spill trajectories. The results demonstrate that the accuracy of the numerical models depends upon the quality of the meteorological input data. In this case, the current fields at the sea surface, derived by ROMS, have been underestimated by the wind fields of the NCEP reanalysis data. An efficient calibration of these wind fields, with data provided by the Gascony buoy (fixed oceanic and atmospheric station), achieves more realistic looking results; this is reflected in the comparison between the buoy trajectory predicted numerically and the tracked movements of the drifting buoy.     

Prediction of wave parameters by using fuzzy inference system and the parametric models along the south coasts of the Black Sea

Forecasting of sea-state characteristics has a great importance in coastal and ocean engineering studies. Therefore, the purpose of this study was to investigate performances of Adaptive-Network-Based Fuzzy Inference System (ANFIS) and several parametric methods in the Black Sea. For this purpose, different fuzzy models with different input combinations were developed for two different wind data sources (TSMS and ECMWF) at two offshore buoy stations. It also aimed to apply several approaches to event-based data sets for wave predictions. Generally, in literature the tendency is to use time series data for wave predictions. In this kind of prediction approach, lagged time series data are taken as inputs and current or future variables are taken as output. In this study, event-based data for each independent storm were extracted from time series data. Simultaneous or concurrent data of wind speed, blowing duration, fetch length and wave characteristics were detected for each single storm. These event data were then used to set up models. The hindcast results were validated with significant wave height and mean wave period data recorded in Hopa and Sinop buoy stations. The performance of developed fuzzy models were also compared with that of four different parametric methods (Wilson, SPM, Jonswap, and CEM methods) applied for two wind data sources at both buoy stations. Finally, it was determined that in the prediction of both wave parameters (H _s and T _z) the ANFIS models (R = 0.66, squared correlation coefficient, and MAE = 0.37 m, mean absolute error, for the best model in prediction of H _s) were more accurate than the parametric methods (R = 0.63 and MAE = 0.75 m for the best model in prediction of H _s).     

Simulation of the oil spill processes in the Sea of Japan with regional ocean circulation model

A simulation of the movement of spilled oil after the incident of the Russian tanker Nakhodka in the Sea of Japan, in January 1997, was performed by a particle tracking model incorporating advection by currents, random diffusion, the buoyancy effect, the parameterization of oil evaporation, biodegradation, and beaching. The currents advecting spilled oil were defined by surface wind drift superposed on the three-dimensional ocean currents obtained by the Geophysical Fluid Dynamics Laboratory modular ocean model (GFDL MOM), which was forced by the climatological monthly mean meteorological data, or by the European Center for Medium Range Weather Forecasts (ECMWF) daily meteorological data, and assimilated sea surface topography detected by satellite altimeter. A number of experiments with different parameters and situations showed that the wide geographical spread of oil observed is not explained by wind drift alone, and that including the simulated climatological currents gives better results. The combination of surface wind drift and daily ocean currents shows the best agreement between the model and observations except in some coastal areas. The daily meteorological effect on the ocean circulation model results in a stronger variability of currents that closely simulates some features of the nonlinear large-scale horizontal turbulent diffusion of oil. The effect of different parameterizations for the size distribution of model oil particles is discussed. Received for publication on July 26, 1999; accepted on Nov. 17, 1999     

基于WRF-SWAN模式的韦帕台风波浪场模拟

为获取更为准确的台风过程波浪模拟结果,将中尺度大气模式WRFD海面以上10 m处风速资料作为驱动风场提供给第三代海浪模式SWAN进行波浪计算,模拟了0713号"韦帕"台风的波浪场过程。模拟和实测资料比较结果表明WRF模式能较好地模拟韦帕台风过程,给SWAN模型提供高精度风场资料,WRF-SWAN模式能够较好模拟韦帕台风过程中海浪的演化和传播。     

岸边集装箱起重机风载荷数值模拟研究

岸边集装箱起重机抗风性能设计是不可缺少的控制性环节。本文对65t-65m岸边集装箱起重机风洞试验的模型进行了计算流体动力学（CFD）数值模拟。通过计算几个典型的风向角和风速工况下起重机风洞试验模型，得到了丰富的流场及压力场信息，并绘制了速度分布和压力分布图。与风洞试验的数值对比，所得误差较小，说明使用CFD数值模拟的方法计算岸边集装箱起重机风载荷是可行的。     

天津港至南排河岸段海域悬沙运动遥感分析

利用Landsat-5/7卫星影像资料和实测含沙量资料,建立天津港—南排河岸段海域悬沙遥感模式,对表层水体悬沙分布及泥沙运动情况进行分析。研究表明,该海域含沙量均呈现从近岸至外海递减,具有明显的层次性;相对较高的含沙区域主要集中在-2m等深线以内,其表层含沙量一般在0.3kg/m3以上;沿岸线走向,含沙量的大小及分布范围总体呈现自北向南有所增大的特点;悬沙分布受季节性影响较大,冬季大风掀沙使得冬季含沙量明显大于夏季;当海域吹向岸风时近岸的含沙量要比吹顺岸风或离岸风时近岸含沙量高。     

风浪流作用下单船艏艉锚泊允许波高的试验研究

研究风浪、浪流和风浪流联合作用对275HP拖网渔船单船艏艉双锚锚泊时锚泊力和运动量的影响。试验结果表明,风浪作用下的锚泊力和横摇角度均大于纯浪作用的情况;流速小于1.0 m/s时浪流作用下的锚泊力大于纯浪作用的情况,而横摇角度则略小于纯浪作用的结果;风浪流联合作用下的艏艉拉力均大于风浪或浪流作用下的拉力值。由于渔船艏艉受风和受流面积的区别,导致艏拉力时流的影响较大,而艉拉力时则风的影响较大。由于流作用时渔船具有的初始横摇角度对其运动具有抑制,从而风浪流联合作用时的横摇角度要略低于风浪作用下的角度值。在本次试验范围内,当港内同时有10级左右风和小于1.0 m/s流速的流共同作用时,建议允许有效波高取0.6 m比较合适。