水轮机固定导叶的涡街模拟与振动分析  

Vortex Shedding Simulation and Vibration Analysis of Stay Vanes of Hydraulic Turbine

作　　者：庞立军[1] 吕桂萍[1] 钟苏[1] 刘晶石[1] 

机构地区：[1]哈尔滨大电机研究所水力发电设备国家重点实验室,哈尔滨150040

出　　处：《机械工程学报》2011年第22期159-166,共8页Journal of Mechanical Engineering

基　　金：国家重点基础研究发展计划资助项目(973计划;2010CB736208)

摘　　要：研究三峡右岸部分机组水轮机固定导叶出水边处的卡门涡街共振问题。根据机组的实际运行情况和产生异常噪声的特点,应用计算流体力学(Computational fluid dynamics,CFD)数值分析技术对固定导叶开展出水边处的涡街振动模拟,建立模拟涡街振动的CFD数值模型,采用Fluent软件实现对卡门涡街振动特性的定量分析;同时采用流固耦合分析方法对固定导叶进行水下动态特性分析,获得结构在水中的固有频率。分析表明,固定导叶的卡门涡街频率与其在水中的固有频率是非常接近的,容易发生耦合并造成局部振动。结合现场振动与噪声测试加以验证,确定产生异常噪声的激振源,找到诱发卡门涡街共振的主要原因。通过对固定导叶不同出水边截面几何形状的对比分析,提出有效预防和消除卡门涡街共振的优化方案。The Karman vortex shedding resonance at the trailing-edge of stay vanes in some units of right bank of Three Gorges Hydropower station is investigated.According to the actual operation of units and the characteristics of abnormal noise,the Karman vortex shedding resonance at the trailing-edge of stay vanes is simulated by using computational fluid dynamics,CFD numerical technology.Based on the CFD numerical model established,quantitative analysis on the vibration performance of Karman vortex shedding is achieved by using the software FLUENT.Then,dynamic behavior analysis of stay vanes underwater is implemented by using fluid-structure interaction method,and natural frequency of structure underwater is obtained.It is shown that the frequency of Karman vortex shedding is very close to the natural frequency of structure underwater.This phenomenon could cause interaction between them and local vibration easily.By validation with the vibration and noise test on site,vibrating source causing abnormal noise and main reasons inducing the Karman vortex shedding resonance are found.Finally,by comparative analysis of different sectional profiles of trailing-edge of stay vanes,the optimization scheme for preventing and erasing the Karman vortex shedding resonance is raised.

关 键 词：固定导叶 卡门涡街共振 数值模型 异常噪声 出水边形状 

分 类 号：TK730[交通运输工程—轮机工程]