不同启动方式对高温过热器出口联箱应力与寿命的影响  

Effects of Different Start-up Modes on the Stress and Lifetime of a Superheater Outlet Header

作　　者：范佩佩 赵永亮[1] 种道彤[1] 刘明[1] 严俊杰[1] FAN Peipei;ZHAO Yongliang;CHONG Daotong;LIU Ming;YAN Junjie(State Key Laboratory of Multiphase Flow in Power Engineering,Xian Jiaotong University,Xi'an 710049,China)

机构地区：[1]西安交通大学动力工程多相流国家重点实验室,西安710049

出　　处：《动力工程学报》2019年第3期184-190,共7页Journal of Chinese Society of Power Engineering

基　　金：国家重点基础研究发展计划资助项目(2015CB251504);国家重点研发计划资助项目(2017YFB0602101)

摘　　要：建立了某600 MW超临界机组高温过热器出口联箱三维有限元模型,针对冷态、温态和热态3种典型启动方式,通过模拟得到联箱瞬态温度场、热应力场、机械应力场及耦合应力场,对比不同启动方式对联箱低周疲劳循环寿命和疲劳损伤的影响。结果表明:耦合应力最大值均出现在筒体内壁面与接管相贯线处;不同启动方式下热应力与机械应力的耦合作用均为相互抵消作用;冷态、温态和热态启动方式产生的疲劳损伤比例为449∶8∶1,可为高温过热器出口联箱的设计和运行提供数据指导。A three-dimensional finite element model was established for the high-temperature superheater outlet header of a 600 MW supercritical power unit.Based on the three typical conditions of cold,warm,and hot start-up,the transient temperature field,thermal stress field,mechanical stress field,as well as coupled stress field of the header were obtained,and the effects of different start-up modes on the low cycle fatigue life and damage of the header were compared.Results show that the maximum coupled stress occurs on the intersecting line between the cylinder inner wall and the pipe joint.The thermal stress and mechanical stress would offset each other in different start-up modes.Moreover,the ratio of fatigue damage among the cold,warm,and hot start-up mode is 449∶8∶1.This study may serve as a reference for the design and operation of high-temperature superheater outlet headers.

关 键 词：高温过热器出口联箱 应力分析 低周疲劳循环寿命 有限元模型 

分 类 号：TK225[动力工程及工程热物理—动力机械及工程]