含沙条件下水力机械空化流动机理研究

项目名称： 含沙条件下水力机械空化流动机理研究

项目编号： No.51269011

项目类型： 地区科学基金项目

立项/批准年度： 2013

项目学科： 水利工程

项目作者： 赵伟国

作者单位： 兰州理工大学

项目金额： 48万元

中文摘要： 自然界中的河流大多都含有一定量的泥沙，因此以提水为目的的泵站和发电为目的的电站中运行的水力机械都面临着输送含沙水流时所造成的磨蚀和空蚀问题。目前对于空化的研究主要基于单相、清水介质，而对含沙水流中的空化流动问题研究较少。本研究拟从固液两相和汽液两相流动理论出发，建立汽固液多相耦合流动的理论模型，并发展适用于含沙水流空化流动的非定常求解方法，其中包含考虑含沙量及颗粒直径影响的空化模型和湍流模型；通过数值方法研究含沙水流空化状态水力机械内部流动机理，得到含沙量及颗粒粒径与水力机械外特性的对应关系；通过实验方法对提出的数值方法进行验证。对于含沙水流中水力机械空化的控制，本项目采用叶片表面加障碍物方法，通过数值和试验方法研究障碍物形状、几何尺寸对水力机械空化性能的影响，为水力机械的设计和空化控制提供理论支持。

中文关键词： 含沙水流；水力机械；空化；数值模拟；试验研究

英文摘要： Rivers in the nature mostly contains a certain amount of sediment. Fluid machineries in pumping stations for the purpose of carrying water and power stations for the purpose of power generation are all facing a serious problem-sediment abrasion and cavitating erosion in sediment laden flow. Research on cavitation is mainly based on single-phase water media and cavitaion in sediment laden flow less. Based on the solid-liquid two phase flow and vapor-liquid two-phase flow theory, a theoretical model of the coupled flow of the vapor-solid-liquid multiphase will be established and unsteady algorithm will be developed for solving cavitation flow in sediment laden flow, which includes cavitation model and turbulence model considering the impact of sediment concentration and particle diameter. Internal flow mechanism of fluid machinery in cavitating state in sediment laden flow will be studied through numerical method and the corresponding relations of sediment concentration and particle size and external characteristics of fluid machinery will be obtained; experimental methods will be proposed to verify the developed numerical method. For cavitation control in fluid machinery in sediment laden flow, obstacles placed on the blade surface will be used. Through numerical and experimental methods, research on the effect o

英文关键词： sediment laden flow；fluid machinery；cavitation；numerical simulation；experimental research