【作者】 潘中奇；

【导师】 杨敏；

【作者基本信息】 天津大学 ， 水利水电工程， 2009， 硕士

【摘要】 海口市的河网水系比较发育,纵横交错,围绕主城区呈现“二横五纵”的分布主格局,其中南渡江是海口市生活用水、工业用水的主要来源,随着经济的发展,用水量增加,上游河道过渡采砂,引发了盐水入侵问题。通过拟建橡胶坝工程来阻挡盐水入侵,改善河口水环境,并提出了城市河网水系水环境改善规划方案,充分利用南渡江的水来改善城市河湖水系的生态环境。应用水动力学和水质数学模型,对水体的水动力特性和盐水入侵情况进行数值模拟,是研究拟建工程对河口水动力特性影响的重要途径。本文通过建立二维水流及盐度数学模型,对研究区域进行了数值模拟,主要的研究内容包括以下几方面的内容。(1)利用南渡江河道断面数据建立数学模型,确定计算的参数,进行数值模拟。对建橡胶坝前后,在上游不同径流流量下,对南渡江河口段水动力特性进行研究,分析比较建坝前后南渡江的水位、流速变化情况,(2)根据海口市的城市河网水系水环境改善规划方案,海口市河网的水动力调整方案分七条线路,通过研究不同优化方案线路河道中的流速、水深与流量的关系,分析优化方案实施后对海口市河网的水动力特性的影响,以河流的生态流速与生态水深为标准来保证一定的生态目标,按照河道生态、环境的需求控制不同路线引水的流量。(3)盐水入侵的数值模拟。通过盐度数学模型模拟的计算结果,得出在不同流量下,盐水入侵的距离,进一步论证橡胶坝工程建设的必要性,也为南渡江河口段的水资源综合利用提供决策依据更多还原

【Abstract】 The River network systems of Haikou city are development, which is vertical and horizontal around the urban zone. The existence and industry water resource of Haikou city is supplied by Nandu river basin. Along with the progress of the economy, much water resource should be offered, and the overage quarrying on the upriver, which arouse the problem of the saltwater intrusion. Owing to this problem, the rubbery dam should be built to block off the intrusion and improve the environment of the bayou. Around the dam, put forward the water area layout projects for improving the water resource.Using the Hydrodynamics and Water Quality Mathematical Model for Numerical Simulation to investigate the hydrodynamic characteristics and the distance of saltwater intrusion, which is an important way to study on the hydrodynamic characteristics for the planning rubber dam around the estuary.This paper establish 2-D Flow Mathematical Model and salinity mathematical model for simulating the study area. The main work of this paper can be concluded as follows:(1) Utilizting the Nandu river cross-section model to build mathematical model, determining the calculation parameters to Numerical Simulation. compareing the pre-and post conditions for building rubber dam, which include water level fluctuation and velocity variation.(2)According to the Improvement Works for Urban Water System on Haikou city, seven river network routes are separated around Nandu river, based on the optimization scheme to analysis the relationships between the velocity、the water depths and the flow rate ,summarizing the influence about the hydrodynamic characteristics for Hankou river network. For the ecological target to guarantee definite flow depth and velocity, using the optimization scheme to afford certain flow rate .(3)By means of the results of salinity mathematical model, can obtain the changes of the distance of salt water intrusion with the different flow rate, which demonstrate the further necessity for building rubber dam, on the other hand to provide decision for the water resources utilization on Nandu river.更多还原