流固热耦合下汽轮机末级叶片破坏规律分析  

Damage Regularity of Last Turbine Stage Blade Under Fluid-solid-thermal Coupling Action

作　　者：何玉灵[1] 王烁 白洁[1] HE Yuling;WANG Shuo;BAI Jie(Hebei Provincial Key Laboratory of Electric Machinery Health Maintenance&Failure Prevention,North China Electric Power University,Baoding 071003,China)

机构地区：[1]河北省电力机械设备健康维护与失效预防重点实验室(华北电力大学),河北保定071003

出　　处：《电力科学与工程》2020年第10期63-69,共7页Electric Power Science and Engineering

基　　金：国家自然科学基金(51777074);河北省自然科学基金(E2020502032);中央高校基本科研业务费(2020MS114、2018YQ03);河北省第三批青年拔尖人才支持计划([2018]-27)

摘　　要：分析了某大型汽轮机末级叶轮在蒸汽流场中的力学响应和叶片失效破坏规律。分析过程基于有限元建模计算进行,充分考虑了流固热多场耦合作用。与其他文献不同的是,通过建立叶轮整体和精确匹配气缸的蒸汽三维模型来实现对叶片真实工作环境的逼近模拟和响应求解;在ANSYS软件Workbench平台对叶轮整体进行了单向流固耦合计算和单向热固耦合计算,分别获得了末级叶片在各耦合下的总体变形及应力、应变响应结果,并对两种耦合的效应进行了对比分析。分析表明,末级叶片叶身中上部及叶片边缘在工作过程中易发生疲劳、破坏,在叶身距叶根2/3处添加拉筋结构可有效增强叶片强度。The mechanical response and blade failure law of the last stage impeller of a large steam turbine in the steam flow field are analyzed.The analysis process is based on finite element modeling and calculation,and the fluid-solid thermal multi-field coupling is fully considered.Different from other literatures,the approximate simulation and response solution in the real working environment of the blade is achieved by establishing the three-dimensional steam model of the whole impeller and the accurately matching cylinder.In ANSYS Workbench,one-way fluid-structure coupling calculation and one-way thermoset-structure coupling calculation were carried out for the impeller as a whole.The overalldeformation data,stress and strain response results of the final stage blade under each coupling were obtained respectively,and the effects of the two kinds of coupling were compared and analyzed.The analysis shows that the middle and upper part of the final blade body and the blade edge are prone to fatigue and damage in the working process and it is suggested to add the stiffener structure at 2/3 of the blade body from the blade root to enhance the strength of the blade.

关 键 词：汽轮机 末级叶片 流固热耦合 破坏规律 

分 类 号：TK14[动力工程及工程热物理—热能工程]