中文摘要：

含沙水水轮机尾水管在运行工况下多存在流态不稳定，以及偏心涡带，从而引起压力脉动和尾水管振动，同时由于转轮出口环量的不均匀，引起尾水管内水流的脱流和撞击，导致空蚀磨损现象，影响水轮机的安全运行。为此，通过商用CFD软件建立含沙水中水轮机尾水管内部多相流动的数学模型，对尾水管加设导流隔板与否进行对比分析，肯定了导流隔板的作用；同时对不同位置导流隔板进行探讨，分析了尾水管水流运动情况和压力脉动。结果表明尾水管直锥段加设导流隔板，在减轻压力脉动方面十分有效。

英文摘要：

Water containing sand hydraulic flow state in the draft tube of Francis turbines under operation condition is more unstable , and the eccentric vortex band ,causing pressure fluctuation and draft tube vibration ,at the same time due to the outlet circulation of runner is uneven ,leading to taking off the flow and impact of the water in the draft tube ,and then leading to the phenomenon of cav-itation erosion and abrasion ,so affecting the safe operation of turbines .Therefore ,in this paper ,through the commercial CFD soft-ware the water containing sand is established inside the draft tube of Francis turbine ,the mathematical model of multiphase flow . This paper compares and analyzes the affirmation of the role of diversion separator .The diversion separator is discussed for different positions at the same time ,analyzes the water of draft tube flow situation and the pressure fluctuation .The result shows that the draft tube straight taper section of adding diversion separator is very effective in reducing pressure fluctuation .