部分进汽下调节级叶顶偏心激振特性研究  

Research on Fluid-induced Vibration Characteristics of the Control Stage with Eccentric Tip Clearances Under Partial Admission Conditions

作　　者：张尧 张万福[1] 顾乾磊 陈璐琪 马凯 李春[1] ZHANG Yao;ZHANG Wanfu;GU Qianlei;CHEN Luqi;MA Kai;LI Chun(School of Energy and Power Engineering,University of Shanghai for Science and Technology,Shanghai 200093, China)

机构地区：[1]上海理工大学能源与动力工程学院,上海200093

出　　处：《动力工程学报》2019年第5期353-359,共7页Journal of Chinese Society of Power Engineering

基　　金：国家自然科学基金资助项目(51875361;51575105;51676131)

摘　　要：建立了某350 MW汽轮机调节级全三维计算流体力学模型,研究部分进汽时不同阀序及阀门开度下转子偏心和叶顶围带对流体激振特性的综合影响规律。结果表明:随着各阀后压力升高,累计质量流量增大,激振力先增大后减小;激振力主要来自叶片内弧,但对于偏心状态下的自由叶片,累计质量流量较小时激振力主要来自叶片顶部;垂直与水平方向上的激振力近似相等;非对角进汽时比对角进汽时的激振力大,其中有、无围带叶片模型分别在开启Ⅰ阀、Ⅱ阀和Ⅲ阀时及非均匀开启四阀时的激振力达到最大值,约占高压转子重力的24%～35%;转子偏心及叶顶围带结构均会导致激振力增大,但也受到进汽阀序、转子偏心方向及两者相对位置的影响;相同工况下,转子偏心时最大激振力约为无偏心时的133.94%,有围带叶片的最大激振力约为自由叶片的150%。Based on the computational fluid dynamics, three-dimensional models were established for the control stage of a 350 MW steam turbine to study the influence of rotor eccentricity and tip shroud on the characteristics of fluid-induced vibration under partial admission conditions with the valves being opened in different combinations and degrees. Calculated results show that with the rise of valve pressure, the accumulative mass flow increases while the fluid-induced force increases firstly and then decreases. The force mainly generates from the inner arc of the rotor blade. However, for the free blades in eccentric state, the force mainly comes from the top of the blade when the accumulative flow rate is relatively small. The fluid-induced force in vertical and horizontal direction is approximately equal in magnitude. Non-diagonal admissions produce larger fluid-induced force, which reaches the maximum for the model with shroud when valves I, II and III are open, and for the model without shroud when all the four valves are non-uniformly opened, sharing 24% to 35% weight of the high-pressure rotor. Both the rotor eccentricity and tip shroud increase the fluid-induced force, but the force is also affected by the partial admission mode, the eccentric direction and the relative position between the two factors. Under same working conditions, the maximum fluid-induced force in eccentric state is about 133.94% of that in un-eccentric state, and the maximum fluid-induced force for the model with shroud is about 150% of that without shroud.

关 键 词：流体激振 部分进汽 偏心 围带 计算流体力学 

分 类 号：TK263[动力工程及工程热物理—动力机械及工程]