超临界锅炉启动分离器疲劳寿命分析  

Analysis of the Fatigue Life of a Separator for Starting Up a Supercritical Boiler

作　　者：张莹[1] 程毅[1] 袁志平[1] 周志磊[1] 

机构地区：[1]南昌大学机电工程学院,江西南昌330031

出　　处：《热能动力工程》2016年第1期66-70,133-134,共5页Journal of Engineering for Thermal Energy and Power

基　　金：国家自然科学基金资助项目(51066005)

摘　　要：通过创建启动分离器的三维实体模型,运用有限元方法模拟超临界直流锅炉的启动分离器在机组冷态启动过程中的温度分布和峰值应力,分析了启动分离器冷态启动中的寿命损耗。结果表明:启动分离器启动过程中,温度最高的区域出现在汽水引入管与启动分离器内部相接处,启动分离器内、外壁温差会大于汽水引入管的内、外壁温差;最大峰值应力出现在汽水引入管和分离器筒体切向出口部位;疲劳应力损坏发生在应力集中部位,其修正后的应力幅对应的循环次数为12 700次,远大于锅炉寿命期内的冷态启动次数,可以确保锅炉安全启动和运行。A three-dimensional entity model for startup separators was established and the finite element method was employed to simulate the temperature distribution and peak stress of a separator for starting up a supercritical once-through boiler during its cold-state startup period and analyze the service life loss in the process of the cold-state startup of the separator. It has been found that during the startup period of the separator,the highest temperature zone emerges at a location to connect the steam-water lead-in tube inside the separator and the temperature difference between the inner and outer wall of the separator is greater than that of the steam-water lead-in tube. The maximum peak stress emerges at a location of the port on the shell of the separator in the tangential direction opened for the steam-water lead-in tube. Damages caused by the fatigue stress always occur at locations subjected to a stress concentration and the number of cycles or frequency corresponding to the stress amplitude corrected totals 12700,far greater than the frequency for starting up the boiler from the cold state during its service life period,therefore,ensuring that the boiler is always safe during its start-up and operation period.

关 键 词：启动分离器 冷态启动 温度场 应力场 寿命损耗 

分 类 号：TK223.4[动力工程及工程热物理—动力机械及工程] TK225