火电机组“热电解耦”后低压末级叶片动应力分析  

Dynamic Stress Analysis on LP last-stage Blades of Steam Turbine for Thermal Electrolysis Decoupling

作　　者：马义良[1] 李宇锋 梁天赋 马小乐 MA Yi-liang;LI Yu-feng;LIANG Tian-fu;MA Xiao-le(Harbin Turbine Company Limited？ Harbin 150046？ China)

机构地区：[1]哈尔滨汽轮机厂有限责任公司

出　　处：《汽轮机技术》2018年第5期343-345,356,共4页Turbine Technology

基　　金：国家科技支撑计划"1000MW高效宽负荷率的超超临界机组开发与应用"(2015BAA03B01-02-02)

摘　　要：电厂"热电解耦"后低压末级叶片处于小容积流量运行状态,叶片流场将发生变化,叶片沿叶高的热力参数将重新分布,汽流在动叶片根部和静叶栅出口顶部区域出现脱离,形成涡流,在小容积流量下,叶片流场涡流分布较多,低压末级叶片动应力会出现"突增现象",此时的动应力比设计工况要大约5～10倍,如果还是按常规算法给定激振力,是算不出动应力"突增现象"。研究了叶片在小容积流量下动应力计算方法,并得到与实验结果趋势相吻合的变负荷动应力曲线。Last-stage blades of LP Steam turbine are in the running state of small volume flow after Thermal electrolysis decoupling. The flow field of cascade channel will be changed greatly,and the thermodynamic parameters will be distributed again along the radial direction of the blade. The steam flow is not only separated from the root of moving blades,but also from the outlet area of the stationary blades,which makes vortex. In the case of small volume flow,there are more vortexes. The phenomenon of dynamic stress＇ sudden increase will occur in LP last-stage blades. Dynamic stress is about 5-10 times than the design condition. If the excitation force is given according to the conventional algorithm,it is impossible to catch he phenomenon of dynamic stress＇ sudden increase. This paper researches the calculation method of the dynamic stress of blade under the small volume flow,and the dynamic stress curve of the variable load is coincident with the trend of experimental results.

关 键 词：叶片 热电解耦 动应力 

分 类 号：TK113[动力工程及工程热物理—热能工程]