平均应力修正法在汽轮发电机组轴系应力计算中的应用  

APPLICATION OF MEAN STRESS CORRECTION METHOD IN SHAFTING STRESS CALCULATION FOR TURBO-GENERATOR SET

作　　者：郭佳雷 庞乐 

机构地区：[1]华电电力科学研究院,浙江杭州310030

出　　处：《热力发电》2012年第2期68-71,共4页Thermal Power Generation

摘　　要：分析了寿命当量法和损伤当量法修正平均应力效应的机理,给出了损伤当量法的平均应力修正公式。以低-发联轴器材料26Cr2Ni4MoV钢为例,利用有限元法(ANSYS软件)计算了变幅和等幅非对称扭应力载荷下危险截面的疲劳损伤情况。结果表明,在计算恒幅非对称循环载荷下疲劳寿命损伤时,2种方法计算精度相差无几;在计算复杂载荷下疲劳寿命损伤时,用平均应力效应的损伤当量法能显著提高疲劳寿命估算精度。The mechanism of corrected mean stress effect in life equivalent method and in damage equivalent method has been analysed,a correction formula for calculating the mean stress in damage equivalent method being given.Taking material of coupling between the low-pressure cylinder and generater,i.e.the 26Cr2Ni4MoV steel,as an example,the fatigue damage of dangerous section under asymmetric loading of constant amplitude and non-constant amplitude has been calculated by using the finite-element method（ANSYS software）.In the event of calculating the fatigue life damage under symmetric cyclic loading of constant amplitude,the difference between calculating precision of two said mehtods is slight,but in the case of caculating fatigue life damage under complex loading,the damage equivalent method with mean stress effect can substantially enhance the evaluation precision of the fatigue life damage.

关 键 词：汽轮发电机组 轴系 26Cr2Ni4MoV钢 应力 损伤当量 疲劳寿命 有限元 

分 类 号：TK268.1[动力工程及工程热物理—动力机械及工程]