河口水质SDKZ模型及其有限元解的稳定性

根据强混合型河口海域的水流条件及边界特点，针对热污染源提出ＳＤＫＺ模型，并对模型有限元法解的稳定性条件进行了分析，通过实际河口海域流速场和温度场的模拟计算年出 ，该模型具有较镐的精度。     

河口海域污染非线性扩散数值解法研究

在分析蛟路江河口海域流态和污染规律的基础上,考虑盐淡水混合河口海域的污染非线性扩散现象,用有限元解法进行数值分析计算,并对数值解的稳定性进行了分析探讨,通过计算值与实测值的比较,验证了该解法具有较好的精度。     

黄茅海河口湾处某核电站取排水口布置分析

受沿岸流、潮流、径流等动力因素影响,河口水域水动力结构非常复杂。基于数值模拟方法,研究了台山海域腰鼓岬角动力结构并优化了某核电厂取排水口布置方案。结果表明,工程布置方案受粤西沿岸流、珠江下泄径流、腰鼓岬角非稳定的辐散与辐合流、珠江河口高盐陆架水过程等复杂动力过程影响;粤西沿岸流、珠江洪季下泄径流及落潮期间的辐散与辐合流结构,均存在明显的西向输运现象,因此新建核电站排水口不宜与西侧台山火电厂排水口过近,而宜向北布置,以避免影响现有电厂取水温升;方案1排水口布置在腰鼓岬角以北,取水口布置在河口高盐低温陆架水区域,是较优方案。其他方案则需加大取、排水口距离或开辟新的热水通道,降低自身排水对取水口的影响,才能使方案成立。     

海洋油气资源占全球资源总量的三分之一

世界海洋蕴藏着极其丰富的油气资源，其石油资源量约占全球石油资源总量的34％。世界海洋油气与陆上油气资源一样，分布极不均衡。在四大洋及数十处近海海域中，石油、天然气含量最丰富的数波斯湾海域，约占总贮量的一半左右；第二位是委内瑞拉的马拉开波湖海域；第三位是北海海域；第四位是墨西哥湾海域；其次是亚太、西非等海域。     

基于ERA5数据的江苏海域风能资源评估

利用欧洲中期天气预报中心（ECMWF）的ERA5风场数据，综合考虑风功率密度的时空分布、稳定性以及资源储量等要素，对江苏海域风能资源进行评估。结果表明，江苏海域多年平均风速和风功率密度总体呈现南高北低、离岸高近岸低的分布趋势。连云港近岸区域风功率密度等级小于2级，3级及以上区域主要分布在远海海域；盐城和南通除岸边潮间带滩涂区域外，大部分区域达到2级或3级，离岸约30 km可迅速提升至4级以上。风功率密度具有较明显的季节性分布特征；盐城南部和南通海域风能稳定性最好，连云港海域风能稳定性相对较差。南通和盐城南部风能资源有效储量最高，盐城北部次之，连云港最低。     

黄河河口淤积、延伸、演变对河道影响的预估计算方法

黄河河口系弱潮强径流型河口,海洋动力所具有的输沙能力小于河道来沙量.因而造成大量泥沙沉积在河口不同区域,河口以上河道受河口淤积、延伸的影响,相应淤积     

维护健康长江河口的对策研究

根据“维护健康长江,促进人水和谐”的治江新思路,提出了长江河口治理必须坚持因势利导、人水和谐的指导思想和在保护中开发利用长江河口的一系列措施和建议,包括科学规划治导线、因势利导整治河道、以航道整治促进经济发展、保护和利用淡水资源、遵循自然规律有序开发滩涂资源、区分功能开发利用岸线、提高河口防洪（潮）能力、呵护河口生态环境等.     

剧烈变化的径流对九龙江河口流动特性的影响

为了认识不同径流与潮流博弈引发的河口流动特性的变化规律,采用数学模型和大型河口物理模型耦合的方法,系统研究了九龙江下游北溪浦南水文站、西溪郑店水文站以下广大河口区域的流场及水位场的变化。结果表明,天然状态下,当九龙江径流为15 540、2 896、374m3/s且河口恰遇典型日天文大潮时,潮流界分别位于甘文尾后的红树林海洋自然保护区、南北中港以及西溪河道的渡头村和北溪河道的科坑村,径流变化可使潮流界上溯约35km;不同径流条件下河口三角洲的南港、中港、北港行洪和纳潮的分流比及流动特性发生显著变化;九龙江葫芦状河口及厦门岛周边存在径流对潮位影响的分界区,厦门岛北支口门区域受九龙江北溪和西溪径流影响很小。     

龙口煤矿海下联合试运转意义大

6月10日，山东龙口煤矿海下首采面试生产成功。作为我国第一次海下采煤，龙口北皂煤矿海域工程汇集了国内外采煤技术之大成：井下人车、海域索道的装备解决了员工远距离作业的体力消耗；中央泵房、变电所、集中皮带实现了无人值守自动化；海域首采面采用了综采放顶煤技术，在世界尚属首次。     

基于遗传算法的入湖河各口水环境容量计算模型及应用

针对传统计算入湖河口水环境容量采用混合区控制方法存在计算量和误差大的问题,提出一种以遗传算法为基础的湖泊污染源控制方法,基于反问题理念将遗传算法与湖泊二维水质模型相结合,仅需调用一次水量水质模型,即可计算入湖各河口的水环境容量。以太湖为例,构建了基于遗传算法的入湖各河口水环境容量计算模型,计算结果表明该模型简便、效率高,获得了太湖主要入湖各河口的COD水环境容量由大到小的排序规律。     

三峡库湾二维随机水质预测模型的研究

在分析香溪河流域污染特点的基础上,建立了一个二维随机水质数学模型,该水质模型将一维水质随机降解模型和二维迁移扩散模型相结合,同时考虑了各水质参数K1,K2,K3和河道横向扩散系数Dy的随机性影响。该模型适用于各种复杂水力条件的排污范围的水体,对于平面二维的任何一个计算点,它都能给出该点水质浓度随机变化的概率分布,用该模型对三峡建库后的香溪河库湾水质进行了预测,其成果可为三峡库区水环境保护及规划治理提供设计数据。     

长江口北支倒灌盐水团对取水口的影响及流量响应规律

为了研究北支倒灌盐水团对南支取水口水质的影响,构建了A、B1模型模拟盐水团对潮位、水质、盐度的影响。经过验证,发现模型水动力模拟结果及盐度模拟结果与实测数据较为吻合,再利用此模型模拟了大江口北支倒灌盐水团对取水口的影响及流量响应规律。模拟结果表明,北支倒灌盐水团在南支活动呈现以半月为周期下移,倒灌盐水团形成于大潮期间,随着潮差的减小,倒灌逐渐减弱,盐水团逐渐下移;由于盐水团下移的影响,在取水口处的潮平均盐度过程线随着时间呈现较为对称的驼峰形状;在同一取水口盐度,不同流量下潮平均盐度过程线的驼峰最高值随着流量增加逐渐变小,与流量呈指数关系,而最高值出现的时间随着流量增大而逐渐提前。可见流量是控制北支倒灌盐水团对取水口影响的关键因素。     

Likelihood of a marine vessel accident from wind energy development in the Atlantic

Offshore wind energy development is planned for areas off the Atlantic coast. Many of the planned wind development areas fall within traditional commercial vessel routes. In order to mitigate possible hazards to ships and to wind turbines, it is important to understand the potential for increased risk to commercial shipping from the presence of wind farms. Risk is identified as the likelihood that an occurrence will happen, and the consequences of that occurrence, should it occur. This paper deals with the likelihood of commercial vessel accidents, because of the development of offshore wind energy along the US Atlantic coast. Using Automatic Identification System (AIS) data, historical shipping routes between ports in the Atlantic were identified, from Maine to the Florida Straits. The AIS data were also used as inputs to a numerical model that can simulate cargo, tanker and tug/towing vessel movement along typical routes. The model was used to recreate present day vessel movement, as well as to simulate future routing that may be required to avoid wind farms. By comparing the present and future routing of vessels, an analysis of potential maritime accidents was used to determine the increased marginal risk of vessel collisions, groundings and allisions with stationary objects, because of the presence of wind farms. The outcome of the analysis showed little increase in vessel collisions or allisions, and a decrease in groundings as more vessels were forced seaward by the wind farms. Copyright © 2015 John Wiley & Sons, Ltd.     

Nonlinear 2D analysis of the efficiency of fixed Oscillating Water Column wave energy converters

This paper reports on the development of a two-dimensional, fully nonlinear Computational Fluid Dynamics (CFD) model to analyse the efficiency of fixed Oscillating Water Column (OWC) Wave Energy Conversion (WEC) devices with linear power take off systems. The model was validated against previous experimental, analytical and numerical results of others. In particular, the simulation results show excellent agreement with the analytical results obtained by Sarmento and Falcão [1] for linear waves in a 2D channel and with previous experiments by others on the interaction between nonlinear waves and a fixed barge. Results are presented for linear waves on the influence of the seaward wall draft and thickness of the OWC device on the resonant frequency and the capture efficiency of the OWC. The key outcome of the present work is that for fully nonlinear waves a substantial decrease in the hydrodynamic capture efficiency of the OWC device was observed with increasing wave height, which represents a significant departure from the linear wave case. The optimal pneumatic damping coefficient for the OWC was also found to be dependent on the wave height. By analysing the magnitude of the first and higher order components of the incident nonlinear waves and the response of the OWC it was found that the first order capture efficiency decreases with increasing wave height, which in turn implies that the OWC hydrodynamic system is fully nonlinear and that the behaviour of an OWC in a nonlinear wave train cannot be accurately represented by the superposition of the linear response to a number of component linear waves. These results have significant implications for the design and operation of practical OWC systems.     

Refinements to the EFDC model for predicting the hydro-environmental impacts of a barrage across the Severn Estuary

This paper presents an investigation of the impacts of a Severn Barrage on the hydro-environment of the Bristol Channel and Severn Estuary using the Environmental Fluid Dynamics Code (EFDC) model with a recently developed Barrage module (EFDC_B). Details are given of a barrage module being implemented into the EFDC model to represent the various hydraulic structures, such as turbines and sluice gates, as deployed along the barrage line. Several cases, both with and without the barrage, have been simulated to investigate the potential changes on the peak water levels, minimum water depths and peak tidal currents arising from a barrage. The impacts of a barrage on the salinity concentration distribution have also been simulated in both 2D and 3D modes. The predicted results showed that the maximum water levels could be significantly reduced, especially downstream of the barrage and for much of the region in the Severn Estuary and that the minimum water depths would be changed so much that there would be 80.5 km² loss of intertidal habitats due to the sitting of a barrage across the estuary. Likewise, the peak tidal currents would be considerably reduced, and by as much as a half in the middle of the main channel. The predicted salinity concentrations results indicated that at high water, the salinity concentrations would be reduced by 1–2 ppt downstream and upstream of the barrage and salinity concentrations in the region near Beachley would be reduced by up to 5 ppt, and that at low water, salinity concentrations would be reduced by 0.5–1 ppt in the middle of the Bristol Channel and by typically 0.5 ppt and 1 ppt downstream and upstream of the barrage, respectively. The predicted results also indicated that salinity concentrations downstream and upstream of the barrage would be under a stable state with slight oscillations all the time due to the effects of the barrage. A comparison between the salinity concentration distributions predicted by the 2D and 3D models indicated that the two models produced similar salinity distributions, especially in the Severn Estuary and in the region between the middle of the Bristol Channel and the seaward open boundary.     

Hydrogen in the seaward advancement of industrial societies

Since the initial impetus of Derek Gregory's landmark analysis of the Hydrogen Economy in 1972, most concepts for producing hydrogen offshore have assumed that the entire product utilization will be onshore. Although delivery to shore is undoubtedly one option, there is another, which is use at sea at or near the site of hydrogen generation.While many of us strive toward the development of hydrogen as tomorrow's fuel, another evolutionary bud is sprouting: our industry is beginning to move seaward. At the same time most signs point to a realization that we are on the threshold of a new social order; a society that is growth-limited by finite energy resources and one that may have to modify its techno-demographic patterns.Existing onshore energy infrastructures must convert to hydrogen at considerable expense and the conversion must be incremental and non-disruptive—no mean challenge. Offshore urban/industrial complexes, on the other hand, could be based upon hydrogen from the beginning. They could thus serve as test and demonstration beds for the eventual adoption of hydrogen as the storable, transportable and ecologically sound fuel base of highly efficient urban/industrial complexes everywhere.This paper explores this option and offers glimpses of future possibilities.     

The economics of hydrogen as a fuel

Second Law costs together with an accounting for the cost of environmental or health hazards constitute Real Costs, i.e. costs seen from the viewpoint of the majority. Time at which the costs of various competing fuels have to be compared is the time at which they will have to be used. This is not that at which they will be competitive compared with the exhausting fuels, but some years (perhaps as much as two decades) earlier.The First Law costs of H₂ from coal are $4.00/MBTU. No other methods compete at this time. Biomass is likely to do so if developed. Photo-oriented methods might do so.Second Law costs are little known and need research. For automotive transportation, H₂ is around 1.5 times more efficient in burning than gasoline. Pollution costs would be 13–30% of the costs of a fuel from coal. H₂ gas storage in cars would add around 30% to these costs.Synthetic gasoline could not be made after 2010 for greenhouse effect reasons. But H₂ could be made from coal until 2040, if CO₂ is rejected seaward. This would have an important effect on amortization considerations. The real costs of H₂ from coal will be around 1/3 the costs of synthetic gasoline from coal.Among the newer concepts for H₂ is radiation of H₂O with direct concentrated solar light.     

综合约束线性系统模型及其实时校正方法的研究

本文根据概念性模型与黑箱子模型各自的优缺点,将二者结合起来构成了一个综合约束线性系统模型,并建立相应的实时校正模型,自动跟踪修正模型的预报误差,组成联机实时洪水预报系统。通过长江三峡风滩以上流域作实时洪水预报验证,取得了较好的精度。