【作者】 程凯； 王恭义； 余德启； 丰镇平； 由小川；

【Author】 CHENG Kai;WANG Gong-yi;YU De-qi;FENG Zhen-ping;Shanghai Turbine Works Co.,Ltd;School of Energy and Power Engineering,Xi’an Jiaotong University;School of Aeronautics and Astronautics,Tsinghua University;

【机构】 上海汽轮机厂有限公司； 西安交通大学能源与动力学院； 清华大学航天航空学院；

【摘要】 汽轮机长叶片的开发是发展大容量汽轮机的关键技术。通过有限元方法对汽轮机叶片的稳态受力进行求解分析,已经形成比较成熟的算法和经验,其精度被工程应用所接受。汽轮机叶片既受到汽流激振产生高周疲劳作用,也受到机组启停影响产生低周疲劳,对其疲劳寿命进行评估是一个复杂而重要的命题。汽轮机整圈阻尼叶片在运行状态下振动模态和响应特性非常复杂,加上汽轮机蒸汽通道中的非稳态流动情况很难获得,因此为了分析叶片寿命而要想获得整圈阻尼叶片在工作状态下的准确的三维动态应力,至今仍是一个难题。在叶片基本CAE分析的基础上,对汽轮机叶片尤其是大型核电汽轮机末级长叶片的寿命尤其是进行了分析,主要对叶片有损寿命分析的流程和特点进行了阐述。更多还原

【Abstract】 Reliability and security are key factors of a long rotating blade in a steam turbine.This paper is devoted to study the fatigue property of a last stage blade in a large-scale steam turbine,especially for the nuclear power plant.In order to study the high/low cycle fatigue life of long rotating blade,firstly,finite element model of a single blade was analyzed by using ABAQUS.The regions concerned in fatigue calculation were captured after the stress distribution was obtained.Furthermore,fatigue tests were carried out on the blade materials,and SN curve was obtained employing least square fitting method.Finally,by combining the results of finite element analysis(FEA) and fatigue tests,some life-predicting method is applied to assess the high/low cycle fatigue life under the condition without initial crack.In addition,preliminary analysis on cycle fatigue life under condition with initial crack was studied as well,by setting initial micro-cracks in the special locations of blade.The results indicated that the blade without initial crack would not break during its very long cycle fatigue life.However,the blade life would decrease sharply if initial crack occurs,which implies that in practical application the crack on the blade should be avoided any way.更多还原