在滨海核电厂设计基准洪水位确定中的风暴潮评价

设计基准洪水位是滨海核电厂选址中的重要参数之一,而风暴潮评价又是设计基准洪水位的主要组成因素.本文还结合目前核电厂的工程实例,就风暴潮评价中存在的问题进行了探讨,并提出了一些建议.     

Enhancing hydrologic modelling through the representation of traditional rainwater harvesting systems: A case study of water tanks in South India

Water tanks as traditional rainwater harvesting systems for agriculture are widely distributed in South India. They have a strong impact on hydrological processes, affecting streamflow in rivers as well as evapotranspiration. This study aims at an accurate representation of water harvesting systems in a hydrologic model to improve model performance and assessment of the catchment water balance. To this end, spatio-temporal variations of water bodies between the years 2016 and 2018 and the months of January and May 2017 were derived from Sentinel-2 satellite data to parameterize the water tanks (reservoir) parameters in the Soil and Water Assessment Tool (SWAT+) model of the Adyar basin, Chennai, India. Approximately 16% of the basin is covered by water tanks. The initial model performance was evaluated for two model setups, with and without water tanks. The best model run was selected with a multi-metric approach comparing observed and modelled monthly streamflow for 5000 model runs. The final model evaluation was carried out by comparing estimated water body areas by the model and remote sensing observations for January to May 2017. The results showed that representing water tanks in the hydrologic model led to an improvement in the representation of the seasonal variations of streamflow for the whole simulation period (2004–2018). The model performance was classified as good and very good for the calibration (2004–2011) and validation (2012–2018) periods as NSE varies between 0.67 and 0.85, KGE varies between 0.65 and 0.72, PBIAS varies between −24.1 and −23.6, and RSR varies between 0.57 and 0.39. The best fit was shown for the high and middle flow segments of the hydrograph where the coefficient of determination (R²) ranges from 0.81 to 0.97 and 0.75 to 0.81, respectively. The monthly variation of water body areas in 2017 estimated by the hydrologic model was consistent with changes observed in remote sensing surveys. In summary, the water tank parametrization using remote sensing techniques enhanced the hydrologic model's efficiency and applicability for future studies.     

柱状危岩体崩塌产生涌浪的物理试验与数值模拟分析

柱状危岩体是三峡库区常见的一种典型地质灾害隐患,其崩塌产生涌浪给库区航运、旅游、生产生活以及人员财产造成巨大威胁和损害。文章基于野外柱状危岩体的成生及运动边界条件,开展了颗粒柱体崩塌产生涌浪的物理试验和数值模拟。结果表明:该数值模型能较好地模拟崩塌涌浪的形成过程、矢量信息以及与水体的相互作用;速度曲线定量地展示了能量的传递;物理试验和数值模拟涌浪高度偏差约3~4 cm;数值模拟堆积区堆积角比物理试验大5%;比前缘运动距离小7%。为柱状危岩体崩塌产生涌浪灾害的预测和预警提供了重要依据。      

Fluid–structure interaction analysis of 3-D rectangular tanks by a variationally coupled BEM–FEM and comparison with test results

A variationally coupled BEM–FEM is developed which can be used to analyse dynamic response, including free-surface sloshing motion, of 3-D rectangular liquid storage tanks subjected to horizontal ground excitation. The tank structure is modelled by the finite element method and the fluid region by the indirect boundary element method. By minimizing a single Lagrange function defined for the entire system, the governing equation with symmetric coefficient matrices is obtained. To verify the newly developed method, the analysis results are compared with the shaking-table test data of a 3-D rectangular tank model and with the solutions by the direct BEM–FEM. Analytical studies are conducted on the dynamic behaviour of 3-D rectangular tanks using the method developed. In particular, the characteristics of the sloshing response, the effect of the rigidity of adjacent walls on the dynamic response of the tanks and the orthogonal effects are investigated. © 1998 John Wiley & Sons, Ltd.     

波浪水槽中随机波的模拟

根据线性系统理论,首先由给定的靶谱模拟海浪信号,再把此信号转换为造波控制输入信号,最后在水槽中指定的截面处产生具有给定靶谱的随机波。这种模拟方法已在青岛海洋大学物理海洋实验室的大型水槽中实现,并取得良好的效果。     

基于ADCIRC-SWAN耦合模式的山东海洋牧场近30年风暴潮和海浪灾害特征分析

基于ADICRC-SWAN耦合模式,文章模拟了山东半岛1985— 2017年的61场风暴潮过程,研究了佳益、明波、富瀚3个海洋牧场的增水与有效波高的分布特征。通过分析3个海洋牧场的风暴增水与有效波高的年极值序列得出,台风风暴潮发生次数最多,但强度没有明显的规律;温带气旋频率最低,但引起的平均增水较高。寒潮引起的风暴潮主要在明波海洋牧场形成高增水,同时在佳益海洋牧场形成大浪。以年极值序列为基础,利用Gumbel极值分布计算了出3个海洋牧场的百年一遇增水与有效波高,增水在明波最高,在佳益最低,而有效波高则相反。进一步考虑波高与增水的联合概率分布,佳益海洋牧场的百年一遇有效波高在增水为50 cm时降低至6.5~7.1 m,在增水150 cm的情况再降至3.9~4.6 m;富瀚海洋牧场的波高在50 cm增水条件下降幅比较明显,在水位增加到150 cm时变化不大,都在2.6~3.2 m;明波海洋牧场在增水为0,50 cm和150 cm时的波高在1.9~2.8 m,与考虑单变量极值情况差别不大。模拟结果对海洋牧场的风暴潮防灾减灾工作有一定参考价值。     

海南省风暴潮预警综合管理平台建设

海南省风暴潮预警综合管理平台通过海域动态专网连接到警戒潮位标志物预警站的智能采集控制器,获取潮位观测和设备运行状态数据,通过数据解析,建立潮位和设备运行监测信息平台中心数据库,在此基础上实现业务管理和应用服务(如数据的监控、统计、查询、图形化分析、报表输出、参数设置、Web客户端等)。临灾前,海南省海洋监测预报中心可依据潮位监测和海洋预报数据,利用风暴潮预警综合管理平台提前对警戒潮位标志物预警站下达预警指令,发布预警信号,警示周边群众及时避险。临灾时,风暴潮预警综合管理平台可为“三防”应急指挥部门提供警戒潮位观测预警站点的风暴增水数据和现场视频画面,为海洋防灾减灾工作和指挥决策提供重要数据支撑和决策依据。     

海岸工程对渤海湾风暴潮高潮位影响分析

渤海湾是全世界受风暴潮灾害最严重的地区之一。近年来渤海湾建设了大量的大型海岸工程,为研究其建设以后风暴潮可能发生的变化,采用大-中-小区域多重嵌套方法,建立渤海风暴潮二维数值模型。以对渤海海域影响最显著的9216、9711台风和2003年10月三次风暴潮为例,对渤海湾大型工程实施前、后的风暴潮过程进行模拟,分析工程实施后风暴潮高潮水位变化,为工程实施可能对风暴潮防护带来的影响提供基础。计算表明,由于沿岸围垦减小海域的纳潮受水面积,海水被挤压抬升,渤海湾海域工程后风暴潮高潮位普遍抬升。在特大风暴潮作用下,水位最大升高可达0.10 m以上,在堤防设计中需引起重视。     

“20110901”温带风暴潮过程天气形势分析及数值预报研究

对2011年9月1日在渤海发生的一次较强温带风暴潮过程的成因及发展情况进行了深入的研究,并对此次温带风暴潮的预报情况进行了较为详细的数值研究分析和总结。从数值预报的结果来看,两套温带风暴潮数值预报模式都表现出较好的预报能力,特别是对于此类移动速度较为稳定的温带系统,预报时效可以延长到24 h左右。通过总结近10年来我国渤海典型温带风暴潮过程的致灾特点发现:冷空气和低压配合对渤海特别是渤海湾产生的温带风暴潮灾害性影响不容小觑,夏半年时更要注意中尺度对流天气叠加在气旋天气系统上对灾害的放大作用。     

Flume tank studies to elucidate the fate and behavior of diluted bitumen spilled at sea

An economical alternative to conventional crudes, Canadian bitumen, harvested as a semi-liquid, is diluted with condensate to make it viable to transport by pipeline to coastal areas where it would be shipped by tankers to global markets. Not much is known about the fate of diluted bitumen (dilbit) when spilled at sea. For this purpose, we conducted dilbit (Access Western Blend; AWB and Cold Lake Blend; CLB) weathering studies for 13 days in a flume tank containing seawater. After six days of weathering, droplets detached from the AWB slick and were dense enough to sink in seawater. The density of CLB also increased, but at a slower rate compared to AWB, which was attributed to the high concentration of alkylated polycyclic aromatic hydrocarbons in it, which are more resistant to weathering. An empirical, Monod-type model was introduced and was found to closely simulate the increase in oil density with time. Such a model could be used within oil spill models.