京杭运河苏北段溢油扩散数值模拟研究

基于Mike21/3SA模块建立京杭运河苏北段溢油扩散数学模型,预测溢油突发事故油膜漂移轨迹和扩散范围。研究结果表明:水动力场、风场对内河溢油扩散有着重要的影响;流速对油膜的漂移过程起主导作用,油膜移动速度随着水流流速的增大而增大;不利风向作用下,油膜下游漂移影响范围明显增大;一旦发生漏油事故,应及时监测溢油河段水流状况与气象条件,及时采取应急救援措施。     

不同风况条件下码头溢油事故影响分析

由于溢油扩散漂移跟时间、地点、数量及相应的风、流等众多不确定的随机因素有关,油膜的漂移过程是极其复杂的。本文从油品装卸码头风险事故识别、溢油事故统计与概率以及源强确定等方面对拟建码头进行分析,针对不同风况条件下,对码头溢油漂移轨迹进行预测分析,结果显示,由风和海流(或河流)引起的油膜运动过程中,在流场、风速等条件一定时,风向是影响溢油运动轨迹的主要因素。为码头的运营以及管理提供技术依据。     

长江宜都港区溢油风险数值模拟

内陆江河航道发生船舶溢油事故对沿岸生态系统与周边居民健康威胁大,为研究长江航道溢油的漂移扩散规律,建立宜昌市宜都港区二维水动力模型并对其流速、水位进行验证后,耦合油粒子模型模拟溢油的运动过程。模拟结果表明:在SSW风向、1.0 m/s风速条件下,丰水期油膜漂移扩散的速度较枯水期快,油膜面积小,对下游取水口以及水源保护区产生持续污染的影响时间短;枯水期油膜在沿岸发生聚集后对下游取水口与保护区产生持续污染影响。模型可为宜都港区的溢油事故应急响应提供理论依据,对模拟预测内陆江河航道的溢油漂移扩散现象具有一定的指导意义。     

瓯江口航道海域溢油扩散数值模拟

首先建立了瓯江口海区平面二维潮流数学模型,根据现场实测资料对该数学模型进行验证.在此基础上对该海区的潮流场进行模拟,为溢油模型提供水动力基础数据,然后利用MIKE21 SA溢油模型对溢油泄露事故进行影响预测.研究结果表明,风的条件因素对油膜漂移轨迹的影响较大.在潮周期的不同阶段发生溢油事故时,溢油油膜漂移轨迹可能完全不...     

基于GNOME和EFDC模型的溢油数值模拟研究——以湄洲湾为例

为了研究溢油发生后的扩散过程,尤其是在近海峡湾内的漂移扩散,采用EFDC(Environmental Fluid Dynamics Computer Code)模型架构了潮流场,采用国际流行的GNOME(General NOAA Oil Modeling Environment)模型读取计算流场并代入设计风速,计算了湄洲湾内湾某假想溢油点发生溢油后,不同工况下的溢油漂移扩散过程。研究结果表明:峡湾内溢油漂移扩散过程在一个潮周期中转流时刻油膜面积迅速扩大;溢油发生于高潮期间的扩散范围远大于低潮,湾底的溢油油膜可以在一个大潮过程遍布整个湄洲湾;风对溢油漂移的影响非常明显,5m/s的风速即能够明显改变溢油的漂移方向。建议在海湾海岸线利用整体规划中增加关键节点区域的溢油拦截设备储备研究,尤其需考虑到常风向的对岸面的溢油防护。     

广西近海溢油扩散数值模拟

利用MIKE 21 HD模块模拟广西近海二维潮流特性,根据实测水文资料对广西近海二维水动力模型进行了验证。应用MIKE 21 OS溢油模块加载广西近海二维水动力数据,建立广西近海二维溢油扩散模型,对溢油事故进行影响预测。研究结果表明,风场、潮流场和溢油事故发生位置对溢油轨迹都有着重要影响。风场是油膜漂移方向的最大影响因素,在不同溢油事故发生位置的工况下,溢油的漂移轨迹和扫海范围可能完全不同。     

海上溢油跟踪定位浮标参数分析及技术优化研究

为提高溢油浮标跟踪海上溢油油膜的精度,基于溢油浮标跟踪油膜的水动力学机理,对溢油浮标的尺寸、重量、海域位置等参数进行分析及优化,研究表明,可以根据浮标应用地理位置、海况及溢油油膜本身的性质,有针对性地选择最优的浮标设计参数,以提高溢油跟踪预测的准确性。     

厦门港嵩屿项目海上溢油数学模拟分析

项目前期论证阶段,通过对油膜扩散理论的研究,在考虑了油膜蒸发、油膜乳化影响的油膜扩展、扩散、迁移和衰减的海上溢油模式,结合水动力数学模型,建立了在潮汐、风浪作用下油膜运动的海上溢油数学模型.应用此模型对厦门港嵩屿码头发生溢油事故后的影响范围进行了模拟,并分析了溢油后油膜运动的几种基本情况.给出了溢油污染区域分布的主要特征.为相关部门控制溢油的影响范围和前期环境影响评价以及应对海上突发溢油事故的污染防治提供了科学依据.     

船舶溢油GIS系统避险设计

为及时掌握船舶海上碰撞等事故导致的溢油事故、溢油分布范围，及时调度船舶救助，运用空间地理信息平台设计溢油规避风险系统。利用溢油扩散预估模型对溢油扩散海域面进行预估和分析，实现对船舶溢油空间分布实时分析，然后运用溢油避险模型模拟溢油事故扩散海域面积并计算，搜取事故中心海域附近各船舶信息并显示在信息系统。模拟结果证明，该研究分析系统可搜取事故影响海域及其附近的船舶及溢油事故油膜扩散空间信息分布评判，并实现溢油事故扩散情形空间平台实时、全方位可监视可预警。     

大型航道工程建设对海域水环境的影响和风险预测

以湛江港航道疏浚工程为例,分析工程中水环境污染的主要来源,并对工程施工期和运营期可能对海域水环境的影响进行预测.结果 表明:在施工期,工程对水环境的影响主要来源于大型机械的运作,主要污染因子是悬浮物;受岛屿和海岸线的影响,航道前段的悬浮物扩散形态与疏浚中段和末端有所区别,由于主航道与海流流向的夹角很小,悬浮物影响区域主要集中在航道周围.船舶溢油事故以操作性事故为主,占总溢油事故的80％以上,溢油影响范围主要受潮流动力和风况的影响;不同潮期、不同风况下的油膜漂移扩散情况不同,对海域影响的面积和严重程度也不同.     

三峡库区溢油预报模型构建及数值模拟

随着三峡库区通航条件改善和船舶流量的不断增加,库区水上溢油风险形势日益严峻.综合考虑风、流的作用,结合水动力方程、溢油漂移扩散的“油粒子”模型等,设计了适用于三峡库区船舶溢油预报模型,并从应急的角度出发,对水动力模型进行并行化改造,提高了预报速度.在此基础上对175 m水位库区的假想溢油事故进行了模拟,初步检验了溢油预测模型的效果.     

珠江口区域海上溢油动态预测信息系统的开发与应用

为了对《珠江口区域溢油应急计划》提供决策支持,在国内外相关研究成果基础上,针对珠江口海域的特点,研究开发了先进实用的"珠江口区域海上溢油动态预报信息系统",综合了三维潮流模型、三维溢油扩散模型、溢油风化模型、应急反应模型、以及电子海图、地理信息系统(GIS)、数据库等关键技术。该系统可以预测模拟并可视化显示海上溢油的漂移扩散和性质变化过程,同时显示环境敏感区和应急人员设备分布等相关信息。实际溢油应用案例表明,该系统的预报模拟结果与现场实际情况完全相符,能有效地提高海上溢油污染事故的应急决策效率。     

Field experiments and new design of a spilled oil tracking autonomous buoy

It is important to forecast the location of oil spills to realize effective and adequate oil spill response operations when huge oil spilsl occur. In order to enhance the accuracy of oil drifting simulations, one needs to obtain the meteorological and oceanographic data around the oil slick. In general, the drifting velocity vector of an oil spill contains a wind velocity vector and a water current velocity vector. SOTAB-II was developed for autonomous tracking of oil slicks drifting on the sea surface. It is equipped with a sail whose size and direction are controllable to drift along with the oil slick autonomously. In addition, SOTAB-II transmits its location and necessary measured data around it to the land base in real-time. The results of field experiments using SOTAB-II with a cylindrical hull brought us the effectiveness of the sail and its control. However, the drifting speed of SOTAB-II was lower than a theoretical speed for the oil slick. In order to overcome this problem, SOTAB-II was redesigned. A yacht shape was adopted to reduce the hydrodynamic drag in the water in the advancing direction. Transverse stability, scales of brake board and sail, maneuverability, and performance of tracking spilled oil on the sea surface were considered in the process of the design.     

Uncertainty in predictions of oil spill trajectories in a coastal zone

A method is introduced to determine the uncertainties in the predictions of oil spill trajectories using a classic oil spill model. The method considers the output of the oil spill model as a function of random variables, which are the input parameters, and calculates the standard deviation of the output results which provides a measure of the uncertainty of the model as a result of the uncertainties of the input parameters.In addition to a single trajectory that is calculated by the oil spill model using the mean values of the parameters, a band of trajectories can be defined when various simulations are done taking into account the uncertainties of the input parameters. This band of trajectories defines envelopes of the trajectories that are likely to be followed by the spill given the uncertainties of the input.The method was applied to an oil spill that occurred in 1989 near Sines in the southwestern coast of Portugal. This model represented well the distinction between a wind driven part that remained offshore, and a tide driven part that went ashore. For both parts, the method defined two trajectory envelopes, one calculated exclusively with the wind fields, and the other using wind and tidal currents. In both cases reasonable approximation to the observed results was obtained.The envelope of likely trajectories that is obtained with the uncertainty modelling proved to give a better interpretation of the trajectories that were simulated by the oil spill model.     

风场作用下趸船区域溢油动态模拟研究

以舟山定海港区某油库码头为背景建立了风场作用下的趸船区域溢油动态模型。针对趸船区域可能产生油品溢漏的位置,对趸船区域的溢油运动情况进行了模拟分析。模拟结果显示,当泄漏油品为柴油(850kg/m3,0.003825Pa·s)、泄漏点宽度为0.5m、油品泄漏速度为1m/s时,受风场作用,发生在趸船附近的溢油事故,其溢漏油品不仅随潮水运动流动,还会大量的在码头与岸线之间的区域及码头两端部附近产生积聚。在进行溢油事故快速控制和污油回收时,需要重点针对该区域进行监控防治。     

Impact of forcing errors in the CAMCAT oil spill forecasting system. A sensitivity study

The CAMCAT oil spill forecasting system is presented in this paper, and an evaluation of the impact of errors in the forcing fields over its forecasts is carried out. The system is formed by several independent modules which provide forecasts of winds, currents and waves to an oil spill module which predicts the evolution of the spill.The typical twin-experiments experience is used paying special attention to a realistic characterization of the errors when perturbing the forcing fields. The results suggest that errors in the wind and current fields are the main limiting factor for the quality of the oil spill forecasts. The pollutant identification is also crucial to determine the final vertical position and characteristics of the product.     

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     

水上溢油应急装备跟踪定位浮标关键技术研究

文中介绍了近年来国内外溢油事故危害及应急技术现状,针对当前海上溢油难以跟踪定位的难题,提出了溢油跟踪定位浮标技术解决方案,采用北斗卫星定位通信为平台,实现海上溢油的全过程、全天候的实时跟踪、监测功能,通过海上试验验证,溢油跟踪定位浮标为海上溢油事故应急快速反应提供了一种有力工具．