弯曲分汊河道航电枢纽布置及通航水流条件试验研究

发布时间：2018-03-17 22:21

本文选题：模型试验　切入点：枢纽布置　出处：《重庆交通大学》2014年硕士论文　论文类型：学位论文

【摘要】：本文依托澧水青山枢纽船闸改造工程项目，采用整体水工物理模型、船模试验和数值模拟相结合的方法，对弯曲分汊河道航电枢纽的平面布置，弯曲分汊河道引航道口门区水流特性，改善弯曲分汊河道引航道口门区的通航水流条件措施等进行了研究。通过对澧水青山枢纽航电枢纽布置研究，得出弯曲分汊河道枢纽建筑物宜采用分散布置。对通航建筑物分别布置在左、右两汊两个方案进行了试验研究，，分析了两种方案的上、下游口门区及连接段通航水流条件，对于复杂地形的弯道口门区通航条件受地形和流量的影响较大，小流量时水深浅通航条件差，随着流量和水深的增大地形对通航条件的影响逐渐减小。原设计左、右汊船闸两个方案的上、下游口门区水流条件都不能满足通航水流条件的规范；对原设计方案进行初步优化后，口门区通航水流条件仍然无法达到规范要求。结合航电枢纽布置、原设计方案试验及初步优化试验分析，左汊船闸方案优于右汊船闸方案，右汊船闸方案进一步优化困难，而左汊船闸方案还有很大的优化空间。将左汊船闸方案作为推荐方案，针对左汊下游口门区附近河床凸凹不平，沙丘、深槽错落，多串沟的复杂地形，采用整平河床、封堵导流墩缺口、延长隔流堤及局部扩宽航槽等措施，进一步优化后左汊下游口门区水流条件达到规范要求。因此，弯曲分汊河道船闸布置应分别通过左、右汊的优化比较来确定。通过建立平均水深二维有限元数学模型，经过验证，数学模型与物模吻合较好，可以用于数值计算。通过对口门区水流条件的数值模拟结果分析，发现回流区域长度与横流强度呈负相关，回流区域越长横流强度越弱。数值模拟成果进一步验证整平河床、封堵导流墩缺口并局部扩宽航槽等措施能够有效地减小口门区横向流速。
[Abstract]:Based on the Lishui Qingshan Shiplock renovation Project, this paper adopts the method of integral hydraulic physical model, ship model test and numerical simulation to arrange the plane of the navigation and power junction of the curved branching channel. The characteristics of flow in the entrance of the approach channel of the curved branching channel and the measures to improve the navigable flow conditions in the entrance area of the approach channel of the curved branching channel are studied in this paper. Based on the study of the layout of the navigation and power hub of the Qingshan Hub in Lishui River, it is concluded that the construction of the curved braided river junction should be dispersed. The experimental study on the two schemes of the navigation structure arranged in the left and right branches is carried out. In this paper, the navigable flow conditions of the upstream and downstream entrance areas and the connecting sections are analyzed. The navigable conditions of the curved entrance areas with complex topography are greatly affected by the topography and the flow rate, and the water depth and shallow navigation conditions are poor when the flow rate is small. With the increase of discharge and water depth, the influence of topography on navigable conditions decreases gradually. The upstream and downstream flow conditions in the upstream and downstream gate areas of the original design of left and right branch shiplock can not meet the requirements of navigable flow conditions. After the initial optimization of the original design scheme, the navigable flow conditions in the entrance area are still unable to meet the requirements of the specification. Combined with the layout of the navigation and power hub, the original design scheme test and preliminary optimization test analysis show that the left branch shiplock scheme is superior to the right branch shiplock scheme. The right branch shiplock scheme is difficult to be optimized further, but the left branch shiplock scheme has great room for optimization. Taking the left branch shiplock scheme as the recommended scheme, the river bed is uneven, sand dunes and deep grooves are dislocated near the downstream gate area of the left branch. In the complex terrain of multi-channel, leveling the river bed, closing the gap of diversion pier, prolonging the barrier and widening the navigation channel, and so on, further optimize the flow conditions of the downstream entrance of the left branch to meet the requirements of the specification. The arrangement of the ship lock in the curved branching channel should be determined by the optimum comparison of the left and right branches respectively. Through the establishment of 2-D finite element mathematical model of mean water depth, it is verified that the mathematical model is in good agreement with the physical model, and can be used for numerical calculation. It is found that the length of the reflux region is negatively correlated with the cross-flow intensity, and the longer the circumfluence region is, the weaker the cross-flow intensity is. Measures such as plugging the gap of diversion piers and widening the channel can effectively reduce the transverse velocity in the orifice area.
【学位授予单位】：重庆交通大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TV632;U612.23

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