多层进水口水力特性数值模拟研究

发布时间：2018-08-07 20:09

【摘要】：为控制或减免水电站发电下泄低温水对下游河段水环境的不利影响，多层进水口已被作为典型措施推荐。与传统单层进水口相比，多层进水口取水断面缩小，进口高程抬高，水流流态更为复杂。在对进水口进行设计时，应保证水流平顺、流态平稳，并尽量减小水头损失。因此，对多层进水口的水力特性进行研究，对进水口体型参数进行优化，对保证电站安全高效运行具有重要意义。本文结合糯扎渡水电站、锦屏一级水电站和光照水电站，采用k紊流模型对其多层进水口水力特性进行了三维数值模拟研究，并通过对所得结果的分析和总结，得出一定规律，为以后多层进水口的设计提供参考。首先，利用糯扎渡水电站多层进水口模型试验结果，水头损失与数值模拟结果吻合良好，验证了采用本文方法模拟多层进水口水力特性的合理性。然后，利用上述方法，对糯扎渡水电站、锦屏一级水电站和光照水电站的多层进水口进行数值模拟研究。研究结果表明，上述水电站进水口的水头损失有所区别，对其原因进行了分析。无门叶取水工况时，从水流流态和流速分布方面分析，糯扎渡水电站和锦屏一级水电站多层进水口的水流流态较好，光照水电站由于其叠梁门墩体型较大，流速变化不平顺。有门叶取水工况时，糯扎渡水电站和锦屏一级水电站多层进水口下游进水室均出现了回流区，光照水电站进水室宽度布置合理，回流情况不明显。上述水电站有门叶取水时，进口前流速均在进口高度范围内较大，说明采用多层进水口取水方案，可以有效实现有选择地取用水库的不同层水体，，对减免电站取水对下游生态环境的负面影响具有积极作用。本文的研究成果可应用于相关的工程。
[Abstract]:In order to control or reduce the adverse effects of low-temperature water discharge from hydropower stations on the water environment of the downstream reach, the multi-layer intake has been recommended as a typical measure. Compared with the traditional single-layer inlet, the intake section of the multi-layer inlet is smaller, the inlet elevation is raised, and the water flow pattern is more complex. In the design of the inlet, the flow should be smooth and steady, and the head loss should be minimized. Therefore, it is of great significance to study the hydraulic characteristics of the multi-layer inlet and optimize the configuration parameters of the inlet to ensure the safe and efficient operation of the power station. Combined with Nuozhadu Hydropower Station, Jinping First-Class Hydropower Station and Illumination Hydropower Station, this paper studies the hydraulic characteristics of multi-layer intake by k turbulence model, and obtains some rules by analyzing and summarizing the results obtained. It provides a reference for the design of multi-layer inlet in the future. First, using the model test results of the multi-layer intake of Nuozhadu Hydropower Station, the head loss is in good agreement with the numerical simulation results, which verifies the rationality of using the method in this paper to simulate the hydraulic characteristics of the multi-layer inlet. Then, the numerical simulation of the multi-layer inlet of Nuozhadu Hydropower Station, Jinping First-Class Hydropower Station and Illumination Hydropower Station is carried out by using the above method. The results show that the head loss of the inlet of the hydropower station is different and the reasons are analyzed. Under the condition of no gate blade intake, the water flow pattern and velocity distribution are analyzed from the point of view of water flow pattern and velocity distribution. The multi-layer inlet of Nuozhadu Hydropower Station and Jinping Grade I Hydropower Station have better flow state, and the flow velocity of Illumination Hydropower Station is irregular because of the larger shape of the laminated gate pier. When there are gate blade intake conditions, the backflow zone appears in the influent chamber of Nuozhadu Hydropower Station and Jinping Grade I Hydropower Station. The width of the inlet chamber is reasonable and the backflow situation is not obvious at the Illumination Hydropower Station. When the gate blade is used for water intake, the velocity of inlet velocity is larger in the inlet height range, which indicates that the multi-layer intake scheme can effectively realize the selective access to different layers of water body of the reservoir. It has a positive effect on the negative impact of water intake on the downstream ecological environment. The research results of this paper can be applied to relevant engineering.
【学位授予单位】：天津大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TV732.1;TV135

【参考文献】