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1.
沙埕港流域物产丰富,目前因电力紧缺多未开发。该港潮汐能源多,地形、地质条件利于建站工程,故拟在百尺门、长屿两处建潮汐电站,并与当地水电等联合运行,可收发电、矿产、水产、航运交通以及农、林、副业等多方面综合利用效益。  相似文献   

2.
In recent years, there has been an increase in interest in renewable energy sources for a number of reasons. A particular interest in tidal energy has developed within the UK due to its numerous sites of high current velocity. In this article a development, based upon previous work, of an existing hydrodynamic computational model is shown which is used to study the potential generation and the physical impacts of tidal stream farms. An idealised geometry is used to study the impacts of installed capacity and general layout of tidal stream farms and a realistic UK west coast model is used to examine the potential of presently proposed in-stream farms.  相似文献   

3.
We examined the respiration rate of Aurelia aurita medusae at 20 °C and 28 °C to evaluate minimum metabolic demands of medusae population in Sihwa Lake, Korea during summer. While weight specific respiration rates of medusae were constant and irrespective to the wet weight (8?C220 g), they significantly varied in respect to temperatures (p<0.001, 0.11±0.03 mg C g?1 of medusa d?1 at 20°C and 0.28±0.11 mg C g?1 of medusa d?1 at 28 °C in average, where Q 10 value was 2.62). The respiration rate of medusae was defined as a function of temperature (T, °C) and body weight (W, g) according to the equation, R=0.13×2.62(T-20)/10 W 0.93. Population minimum food requirement (PMFR) was estimated from the respiration rate as 15.06 and 4.86 mg C m?3 d?1 in June and July, respectively. During this period, increase in bell diameter and wet weight was not significant (p=1 in the both), suggesting that the estimated PMFR closely represented the actual food consumption in the field. From July to August, medusae grew significantly at 0.052 d-1, thus the amount of food ingested by medusae population in situ was likely to exceed the PMFR (1.27 mg C m?3 d?1) during the period. In conclusion, the medusae population of higher density during June and July had limited amount of food, while those of lower in July and August ingested enough food for growth.  相似文献   

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斋堂岛潮汐能发电动态脐带缆线型设计与分析   总被引:2,自引:0,他引:2  
潮汐能是一种清洁能源,利用潮汐能发电是目前亟待开发的一种发电方式。潮汐能发电海上作业的主要输电装置是脐带缆,在浅水海域动态脐带缆随发电装置的运动幅度特别大。为了解决这一问题,采取了一种新的脐带缆敷设方式,锚缆连接的方式。利用Orcaflex软件进行模型建立和模拟计算,通过多次模拟和比较,得到脐带缆的最佳连接方式。  相似文献   

7.
滨海电厂钢筋混凝土腐蚀防护应用   总被引:1,自引:0,他引:1  
刘刚  张奎志  韩冰 《海洋科学》2005,29(7):91-93
某滨海电厂钢筋混凝土结构在海洋大气环境中腐蚀较重,通过分析已破坏的混凝土,确定腐蚀原因主要是二氧化碳腐蚀和氯离子腐蚀,采用TPEI——乳液砂浆和喷射混凝土两种方案,对钢筋混凝土结构进行修复,确保电厂设施正常安全运行。  相似文献   

8.
文章为解决水平轴潮流能发电系统在低于设计流速下叶轮能量捕获效率低的问题,运用最大功率跟踪控制理论及叶轮与变量泵传动轴力矩平衡方程,建立了变量泵反力矩参考值模型,设计了间接速度控制的压力反馈加转矩控制系统,通过小范围内调节变量泵排量,实现叶轮最大功率捕获。整个系统的性能在自动化工作室(automation studio)中进行了仿真测试,实验样机也进行了海上试验。仿真测试和海试结果显示,该控制系统工作稳定性好,仿真和海试时叶轮的捕获功率系数分别在0.35和0.33附近波动,相比不加控制,分别增加了约0.03和0.05,提高了叶轮的捕获效率,验证了控制系统的有效性。  相似文献   

9.
厦门筼筜湖纳潮排污能力研究   总被引:4,自引:0,他引:4  
自 1 971年围垦后 ,厦门港成为内湖 ,没有海水进出交换 ,从而积蓄多种有机污染物和重金属 .但自从 1 984年采取纳潮排污后 ,该湖水质有所改善 .本研究于1 999年主要对湖水质进行调查和评价 .结果显示污染物含量虽然有所降低 ,但仍属于污染状态 .其纳潮排污 ,每天可排放出 :石油烃 40 .8kg ,有机氯农药 0 .0 1 1kg ,铜 4.54kg ,铅 0 .2 84kg ,锌 1 1 .97kg ,镉 0 .3 6kg ,汞 0 .0 1 1kg .由于湖水水质仍未完全改善 ,非常有必要继续进行监测 .  相似文献   

10.
收集了近年来鳌江口附近海域多个工程不同阶段5个潮位站的3-5年潮位实测数据和部分海流实测资料,通过对鳌江口附近海域的不同年份的水位资料进行潮汐调和常数分析,鳌江近海海域主要为半日潮区,其中M2分潮的振幅在170~193 cm;迟角在260°~280°之间,这些站的2007年、2010年、2011年调和常数分析结果相比,主要的半日分潮M2、S2、N2,全日分潮K1、O1及浅水分潮M4、MS4、及M6等分潮振幅、迟角的最大变化分别在1.8~4.4 cm和3°~7°之间。在初步掌握了鳌江口潮汐潮流特征的基础上,采用无结构的三角形网格和有限体积法的FVCOM海洋数值模型,进行模拟结果验证,计算结果与实测数据符合良好。构建重点年份建设工程合拢产生新的岸线水深的潮汐潮流场,刻画鳌江口建设工程的叠加影响。  相似文献   

11.
Tidal flooding and surface drainage patterns have often been used to describe mangrove species zonation. However, in mangrove forests exhibiting little topography, ambiguous species distributions and/or few species, such approaches are ineffective. We identified four physiognomic mangrove forest types (Riverine, Fringing, Overwash and Basin) at Coombabah Lake, a tidal lake in southeast Queensland, Australia and investigated tidal flooding patterns using synoptic surveys of tidal observations at the local Standard Port combined with local water depth observation. Subsequently three sub-types of the basin forest type were identified: (1) Deep Basin Forest with mature trees, ∼50 cm standing water and ∼3 tides per year; (2) Medium Depth Basin Forest with intermediate tree development, ∼15–30 cm standing water and 20–40 tides per year; and (3) Shallow Basin Forest with relatively recent mangrove establishment, 5–15 cm standing water and ∼80 tides per year. These three basin sub-types were found to flood at different tide heights with the Shallow Basin flooding for tides above mean high water springs and the Deep Basin flooding only for tide heights approaching the highest astronomical tide. We propose that these basin types represent a succession in mangrove forest development that corresponds with increasing water depth and tree maturation over time. The succession not only represents increasing age but also change in basin substrate composition. This is manifest as increasing pneumatophore density and an increasing area of basin surface occupied by contiguous pneumatophore cover. As a result, it seems that mangrove development is able to modify tidal flooding into the basin by increasingly impeding water movement.  相似文献   

12.
In September 2008, Hurricanes Gustav and Ike generated major storm surges which impacted the Lake Pontchartrain estuary in Louisiana. This paper presents analyses of in situ measurements acquired during these storm events. The main data used in the analyses were from three bottom mounted moorings equipped with conductivity, temperature, and depth sensors, acoustic Doppler current profilers (ADCPs), and a semi-permanent laterally mounted horizontal acoustic Doppler profiler (ADP). These moorings were deployed in the three major tidal channels that connect Lake Pontchartrain with the coastal ocean. A process similar to tidal straining was observed: the vertical shear of the horizontal velocity was negligible during the inundation stage, but a shear of 0.8 m/s over a less than 5 m water column was recorded during the receding stage, 2–3 times the normal tidal oscillations. The surge reached its peak in the Industrial Canal 1.4–2.1 h before those in the other two channels. The inward flux of water lasted for a shorter time period than that of the outward flux. The inward flux was also observed to have much smaller magnitude than the outward flux (∼960–1200 vs. 2100–3100 million m3). The imbalance was believed to have been caused by the additional water into Lake Pontchartrain through some small rivers and inundation over the land plus rainfall from the hurricanes. The flux through the Industrial Canal was 8–12%, while the flux through the other two tidal passes ranged between 17% and 70% of the total, but mostly split roughly half-half of the remaining (∼88–92% of the total).  相似文献   

13.
近年来,潮流能能量转换技术发展迅速,但大型潮流发电机组基础结构方面的研究和应用还并不多见。针对潮流能电站基础结构在抗弯抗剪强度、桩径尺寸方面的特殊要求,结合我国潮流能富集区海底多为浅覆盖层或裸露基岩、且地形复杂的情况,提出了一种新型模块式嵌岩灌注桩基础结构。该基础结构的嵌岩灌注桩通过在桩内布置环形钢板箍和钢筋束来增强抗剪抗弯能力,使其在常规桩径即可满足潮流能电站的支撑要求,减少了对发电水流断面的阻挡;各主体灌注桩可通过横撑、纵撑和斜撑连接构成模块式基础,以适应不同地形条件、不同机组数量和安装方式的要求。新型模块式嵌岩灌注桩基础结构在LHD联合动能公司3.4 MV潮流发电项目中进行了首次应用,获得了良好的使用反馈。  相似文献   

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15.
The invasion of Mont-Saint-Michel Bay salt marshes (France) by a grass species (Elymus athericus) has led to important changes in vegetation cover, which is likely to modify the habitat for many invertebrates. Some of them constitute the main food items for several fish species, such as young sea bass (Dicentrarchus labrax) and sand goby (Pomatoschistus minutus), that feed in salt marsh creeks during high tides. As a result, fish nursery functions of salt marshes could be modified by the E. athericus invasion. In order to test this hypothesis, gut contents of the two most abundant fish species (sea bass and sand goby) were compared before and after E. athericus invasion in the same salt marsh creek and using the same methodology. The accessibility and availability of the main food item, the semi-terrestrial amphipod Orchestia gammarella, were estimated and compared between invaded (dominated by E. athericus) and original areas (dominated by Atriplex portulacoides). Gut content analysis showed a significantly greater percentage of fish leaving with empty guts from E. athericus areas than from A. portulacoides areas. The sea bass diet composition study showed a major shift in the relative importance of the main food items: before E. athericus invasion, diets were dominated by the semi-terrestrial species O. gammarella, whereas after the E. athericus invasion they were dominated by a marine mysid Neomysis integer. The same trend was found for sand gobies, with a shift of the main food item from O. gammarella before invasion to the polychaete Hediste diversicolor after invasion. These trophic changes may be explained by the lower accessibility and availability of O. gammarella in invaded communities than in natural ones. The E. athericus invasion, observed throughout northern Europe, is thus likely to disturb trophic function of natural salt marshes for fish. This preliminary study of the E. athericus invasion is also an illustration that invasive species are an urgent problem in conservation biology.  相似文献   

16.
徐啸 《台湾海峡》2005,24(4):455-462
本文首先介绍了潮汐水流整体物理模型的作用和功能,讨论目前在厦门海港公园建设厦门潮流模型实验室的意义和作用.通过对国内一些类似大型实验室情况的介绍,提出厦门潮流模型的设计方案;根据实际需要,建议分两期实施.最后指出,物理模型试验是非常专业化的工作,模型馆正常运转的关键是运作体制和人才培养.  相似文献   

17.
为了对欧洲某潮汐电站蓄水砂芯防波堤坝断面进行设计优化,从工程环境、设计要求、断面结构选择、结构稳定性优化、施工和工程造价等方面进行对比分析研究。结果显示,高潮差、长周期波条件下石头围埝方案的砂芯防波堤坝断面满足该项目优化设计要求,该结构断面为类似工程项目提供借鉴和参考。  相似文献   

18.
收集了近年来鳌江口附近海域多个工程不同阶段5个潮位站的3~5年潮位实测数据和部分海流实测资料,通过对鳌江口附近海域的不同年份的水位资料进行潮汐调和常数分析,鳌江近海海域主要为半日潮区,其中M2分潮的振幅在170 cm~193 cm;迟角在260°~280°之间,这些站的2007年、2010年、2011年调和常数分析结果相比,主要的半日分潮M2、S2、N2,全日分潮K1、O1及浅水分潮M4、MS4、及M6等分潮振幅、迟角的最大变化分别在1.8 cm~4.4 cm和3°~7°之间。在初步掌握了鳌江口潮汐潮流特征的基础上,采用无结构的三角形网格和有限体积法的FVCOM海洋数值模型,进行模拟结果验证,计算结果与实测数据符合良好。构建重点年份建设工程合拢产生新的岸线水深的潮汐潮流场,刻画鳌江口建设工程的叠加影响。  相似文献   

19.
The principal character of the tidal exchange process is neither diffusion nor advection, but a third category of transport, “Massenaustausch”, which appears in the space/time averaged transport. The exchange process can be divided into four fluxes: the flux of standing eddies, the flux of tidal exchange, the flux of tidal eddies and the flux of local eddies. The results of observations at the entrance channel of Kumihama-Bay show a typical example of transport dominated by tidal exchange. The tidal exchange ratio defined by Parkeret al. (1972) applies to the process of exchange between the outflowing watermass and the surrounding watermass outside of the bay mouth, but this should also be considered as being coupled with the ratio for the process of exchange between the inflowing watermass and the surrounding watermass inside of the bay mouth. These two exchange ratios can be combined into a single exchange ratio which describes the exchange process between the outer watermass and the bay water.  相似文献   

20.
The effects of the coastal boundary geometries on the tidal currents and the tidal mixing are studied mainly on the basis of hydraulic model experiments. Mizushima-Nada Sea, which is located in the central part of Seto Inland Sea, and the whole Seto Inland Sea were chosen as the prototypes.Currents and eddies geometrically induced in the tidal currents and in the ocean currents have significant effects on the water exchange, from small scales to meso scales, in the bays and near-shore regions of the ocean.As to small scale phenomena near irregular coastal boundaries such as river mouths, headlands and harbors, tidal currents produce organized eddy currents of the width scale. They are important to the temporary flushing and the local redistribution of the river water or the waste water.As to phenomena of larger scales, the tidal currents produce rather steady residual circulations in each part of the Inland Sea, due to the non-linear effects of the oscillating component. They are controlled by the geometry of the sea as separated by a narrow strait. These horizontal circulations of about 20 km in scale become the main mechanism of the water exchange in the Inland Sea. The one-dimensional dispersion coefficient due to these circulations is proportional to the product of the diameter and the current velocity of the circulations. The proportional constant takes the value of 0.40.5.  相似文献   

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