汽轮机叶顶间隙汽流激振力的脉动规律研究  

Study on the Pulsation Law of Steam Excitation Forcein Blade Tip Clearance of Steam Turbine

作　　者：曹加胜 李盼[2] 曹丽华[2] 司和勇 CAO Jia-sheng;LI Pan;CAO Li-hua;SI He-yong(Beijing Electric Power Economic Technology Research Institute Company Limited,Beijing 100055,China;School of Energy and Power Engineering,Northeast Electric Power University,Jilin 132012,China)

机构地区：[1]北京电力经济技术研究院有限公司,北京100055 [2]东北电力大学能源与动力工程学院,吉林132012

出　　处：《汽轮机技术》2020年第5期346-350,338,共6页Turbine Technology

摘　　要：采用理论方法计算静偏心情况下汽轮机叶栅内的汽流激振力,同时应用数值模拟的方法研究叶顶汽封内不均匀流场诱导下的激振力的变化规律。研究发现:转子偏心时,叶栅内的汽流激振力随叶顶径向间隙的增加而减小,随轴向间隙的增加而增大。而汽封流场诱导的汽流激振力由于汽封腔室内的螺旋状涡随时间涡动而呈现周期性变化。转子偏心距的增加,不但使汽流激振力的波动幅度变大,也增大了汽流激振力方向的变化幅度,致使叶顶端区的不稳定性增强。A theoretical method is used to calculate the excitation force of cascade under static eccentricity in the steam turbine,and a numerical simulation method is used to study the variation of excitation force induced by uneven flow field in blade tip clearance.It is found that when the rotor is eccentric,the steam excitation force of cascade decreases with the increase of the radial clearance,and increases with the increase of the axial gap at the blade tip.However,the excitation force induced by the seal flow field changes periodically due to the spiral vortex in the cavity with time.The increase of rotor eccentricity not only increases the fluctuation amplitude of the excitation force,but also increases the variation amplitude of its direction,which leads to the instability in the top zone of the blade.

关 键 词：汽轮机 转子偏心 汽流激振力 理论计算 数值模拟 

分 类 号：TK263[动力工程及工程热物理—动力机械及工程]