定向结晶涡轮叶片低循环寿命分析及结构优化  

Low Cycle Fatigue Life Analysis and Structure Optimization of Directional Crystallization Turbine Blade

作　　者：魏佳明 王博 蓝吉兵 隋永枫 WEI Jia-ming;WANG Bo;LAN Ji-bing;SUI Yong-feng(Hangzhou Steam Turbine&Power Group Co.Ltd.,Central Research Institute,Center,Hangzhou,China;Zhejiang Gas Turbine Innovation Center,Hangzhou,China,Post Code:310022;Zhejiang Rancon Turbine Innovation Co.Ltd.,Hangzhou,China,Post Code:311199)

机构地区：[1]杭州汽轮动力集团有限公司中央研究院,浙江杭州310000 [2]浙江省燃气涡轮机械制造业创新中心,浙江杭州310022 [3]浙江燃创透平机械股份有限公司,浙江杭州311199

出　　处：《热能动力工程》2020年第1期44-48,共5页Journal of Engineering for Thermal Energy and Power

基　　金：杭州市科学技术委员会重大科技创新专项《先进50 MW等级燃气轮机数字样机设计》(20172011A02)。

摘　　要：为保证涡轮叶片的安全性,需要对叶片进行强度分析及寿命预测。以某定向结晶涡轮冷却叶片为例,首先采用三维流热固耦合方法获得叶片温度场分布,然后基于Hill屈服准则,对叶片进行热弹塑性应力应变分析,最后采用带平均应力修正的Morrow公式得到叶片低循环疲劳寿命,并基于计算结果,对局部区域进行结构优化。结果表明:叶身与平台转接圆角吸力面前段(区域1)和吸力面尾缘段(区域2)温度高且应力大,将其作为考核点,两处区域低循环寿命分别为15669和2349。根据工程设计经验,对区域2提出了两种优化方案,其中大圆角设计(R=10)使该点等效应力降低9.9%,低循环疲劳寿命增加157.5%。Gas turbine blades are operated under the elevated temperature and corrosive environment,and susceptible to cracking due to fatigue.In order to ensure the safety of turbine blades,it is necessary to carry out the strength and life prediction analysis.With a directional crystallization turbine blade with cooling structure as an example,the blade temperature field is obtained by a three-dimensional fluid-thermal-solid coupling method.Then the thermal-elastic-plastic stress analysis of blade is carried out based on Hill yield criterion.The low cycle fatigue life of blade is calculated by Morrow formula with average stress correction.Based on the results,the local structure optimization is conducted to achieve a longer operation life.The results show that,the critical points are near the front chord(Zone1)and rear chord area(Zone 2)of suction surface and the transition corner of platform,and the low cycle fatigue life is 15669 cycles and 2349 cycles,respectively.Based on the engineering design experience,two optimization schemes are proposed for Zone 2.The big fillet(R=10)design reduces the equivalent stress by 9.9%and increases the low cycle fatigue life by 157.5%.

关 键 词：Hill屈服准则 流热固耦合 热弹塑性 低循环疲劳寿命 结构优化 

分 类 号：TK14[动力工程及工程热物理—热能工程]