【作者】 刘倩颖；

【导师】 王平义；

【作者基本信息】 重庆交通大学 ， 水力学及河流动力学， 2010， 硕士

【摘要】 河流交汇口区域水流紊乱,泥沙冲淤变化大,通航条件极其复杂。加上汇合口上游水利枢纽修建后,来水来沙条件发生重大改变,枢纽日调节和大坝泄洪对汇合口航道通航条件将产生严重影响。因此,研究汇合口的水沙运动特性及上游水利枢纽的运行对汇合口通航水流条件的影响具有重要意义。本文结合西部交通建设科技项目“长江上游干支流汇合口通航水流条件及整治技术研究”,在回顾汇合口水沙运动研究成果的基础上,选择长江上游沱江汇合口为依托工程,制作了比尺为1：100的正态河工模型,进行了定床和动床试验验证。通过模型试验和理论分析,系统研究了自然来水、向家坝日调节和大坝泄洪情况下沱江汇合口的水力特性及向家坝枢纽泄洪对汇合口河床冲淤变化的影响。详细分析了汇合口纵向、横向水面线、流速分布随汇流比的变化特点；揭示了汇合口水流脉动动能和相对紊动强度在不同流量组合下的分布规律；得出了向家坝枢纽泄洪对沱江汇合口通航水流条件和河床的冲淤变化影响较小,基本能满足通航要求。更多还原

【Abstract】 In the confluent area, flow pattern is tangled, the changes of sediment erosion and deposition are big, and the condition of navigation is complex. Besides, with the construction of hydraulic engineering complex in the upper reaches of confluent area, the conditions of incoming water and sediment will change greatly and the hub daily regulation and the dam flood discharge will have serious implications for the channel conditions. So it is of great significance to study that the water-sediment movement characteristics on the confluence and the operation of upstream hydraulic engineering complex have a great impact on the navigation flow conditions.This paper was carried out from the western communication construction of the "study on the technology of navigation flow condition and regulation in confluent area of the upper reaches of the Yangtze River". In the basis of reviewing the research results on the saliva sediment movement, Tuojiang confluent area is selected as a support project, a undistorted river model with the scale for 1:100 is made, and the fixed bed and the mobile bed experiments are carried on. Through the model text and theoretical analysis, the hydraulic characteristics on the Tuo River confluence affected by the natural runoff, Xiangjia Dam daily regulation and dam flood discharge are studied systematically and the change in scour and fill of bed on the confluence is affected by Xiangjia Dam hub flood discharge. The longitudinal and transversal water surface profiles and the distribution characteristics of velocity affected by confluent ratios are analyzed in detail. The distributions of fluctuating kinetic energy and relative turbulent intensity on the different discharge are mainly studied. It is found that Xiangjia Dam hub flood discharge has little effect on the navigation flow conditions and the changes in scour and fill of bed on the Tuo River confluence and it can basically meet the navigational requirements.更多还原