海湾水库底边界层对水体突然泛咸的双重影响机制与效应

项目名称： 海湾水库底边界层对水体突然泛咸的双重影响机制与效应

项目编号： No.51279075

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 水利工程

项目作者： 高增文

作者单位： 青岛大学

项目金额： 70万元

中文摘要： 海湾水库在运行管理中存在"多年库水盐分达标，而个别时段突然泛咸"的特殊现象，水体的突然泛咸限制了海湾水库在缓解滨海地区水资源短缺中的重要作用。课题从海湾水库具有的"咸化底质-厚浓度边界层-淡水表层"三层结构入手，在中型水槽、大型环形水槽等模拟实验中通过边界层流速与电导率垂向剖面的同步高分辨率测试，密度分层稳定性评价、界面盐分扩散通量准确计算、数值模拟等方法，重点研究：⑴ 边界层的阻滞、盐分富集效应及水库取水与库水盐分达标的关系；⑵ 具有显著密度与粘度梯度的厚边界层混合发生的条件；⑶ 沉积物释放盐分对水质影响的时间尺度。明确边界层的混合尺度与水体突然泛咸的关系，揭示海湾水库底边界层对水体泛咸的双重影响机制。在此基础上，提出在水库的不同时期采取相应的调控边界层盐分蓄积的对策，为滨海地区水资源的"开源"决策、为海湾水库水体咸化的防治提供新思路和理论依据。

中文关键词： 海湾水库；咸化；浓度边界层；混合；沉积物

英文摘要： The salinity in a estuary reservoir usually tends to meet the standard of industrial water for several years, but it would abrupt salinization under special environmental conditions. This issue of abrupt salinization restricts the key role of estuary reservoirs in alleviating water crisis for coastal areas. The project explores the mechanism of water salinization by charactering the three layer structure, including salinization sediment, thick benthic boundary layer and fresh surface layer. The velocity and conductance for the benthic boundary layer is monitored with high resolution on vertical transects in the moderate tank and large annular flume experiments, and then the stability of density stratification and the interfacial flux of salt are quantified. The proposed research is focus on (1) effects of the resistance and salt-enrichment of benthic boundary layer, and taking water from reservoir on the quality of surface water; (2) mixing conditions of boundary layer with obvious gradients of density and viscosity; (3) effects duration of salts released from sediments on water quality. The goal of the project is to explore the relationship between the length scale of the vertical overturning and the degree of abrupt salinization, and to elucidate the dual influence of the benthic boundary layer on water salini

英文关键词： estuarine reservoir；salinization；concentration boundary layer；mixing；sediment