河口最大浑浊带形成的动力模式和数值试验  

The dynamic model and numerical experiment of estuarine maximum turbidity zone

作　　者：朱建荣[1] 傅德健[1] 吴辉[1] 戚定满[2] 

机构地区：[1]华东师范大学河口海岸国家重点实验室,上海200062 [2]交通部科学研究院河口海岸科学研究中心,上海201201

出　　处：《海洋工程》2004年第1期66-73,共8页The Ocean Engineering

基　　金：国家自然科学基金重点资助项目(40231017);高等学校优秀青年教师教育和科研奖励基金资助项目;上海市曙光学者计划资助项目(99SG12)

摘　　要：应用改进的ECOM模式,耦合泥沙输运模型,研究理想河口最大浑浊带形成的动力机制。河口最大浑浊带位于滞流点处,上下游余流均向该处输运泥沙,造成该处泥沙汇合,而由流场辐合产生的上升流又使该处的泥沙不易落淤。南岸(河口东向)的泥沙浓度比北岸高,最大浑浊带位于南岸,这是由于盐水入侵带来的高盐水位于北岸的底层,其斜压效应使底层的环流由北向南流动,把底层高浓度的泥沙向南岸平流,聚集于南岸底层。除上游河流泥沙来源外,强大的涨落潮流冲刷床面,使沉降于床面的泥沙再次悬浮,成为余流输运泥沙的来源之一。Using the improved ECOM model and coupling the sediment transport model, the dynamic mechanism of estuarine maximum turbidity zone in an idealized estuary is studied in this paper. The estuarine maximum turbidity zone is located at the stagnation point. Both the up-stream and down-stream residual currents convey sediments to the stagnation point that induces the convergence of sediments, and the upwelling current induced by the convergence of flow field makes sediment difficult to settle down near the stagnation point. The high-salinity water brought by the salt water intrusion lies in the bottom layer of the north coast, and its baroclinic effect induces the bottom current to flow from north to south, conveying horizontally the high concentration sediment from north to south coast, which converges at the bottom layer of the south coast, so the sediment concentration at the south coast is larger than the one at the north coast and the maximum turbidity zone lies in the bottom of the south coast. Besides the source of up-stream sediment from the river, the powerful flood and ebb current scour the river bed and make the sediment re-suspend, which provides the one of the sediment sources for the residual current transport.

关 键 词：理想河口 三维模式 河口最大浑浊带 数值试验 

分 类 号：P731.22[天文地球—海洋科学]