基于损伤力学的凿岩机活塞疲劳寿命仿真研究  

Simulation Research on Drill Piston Fatigue Life Based on Damage Mechanics

作　　者：罗春雷[1] 闵金才 程后旗 李立成[1] LUO Chun-lei;MIN Jin-cai;CHENG Hou-qi;LI Li-cheng(State Key Laboratory of High Performance and Complex Manufacturing, Central South University, Changsha Hunan 410083, China)

机构地区：[1]中南大学高性能复杂制造国家重点实验室,湖南长沙410083

出　　处：《计算机仿真》2017年第11期395-399,共5页Computer Simulation

基　　金：国家高技术研究发展计划项目(863计划)(SS2012AA041809);高性能复杂制造国家重点实验室自主研究课题(zzyjkt2014-08)

摘　　要：针对传统的断裂力学无法定量估算液压凿岩机活塞的疲劳裂纹萌生寿命,对冲击活塞运用损伤力学-有限元仿真方法进行疲劳裂纹萌生寿命仿真研究。首先运用Ansys软件对冲击系统进行动力学分析,得出冲击碰撞过程中活塞的应力应变变化规律并确定危险点位置为活塞端面靠近外圆处,随后提取危险点处的应力应变谱响应,结合材料S-N曲线和损伤力学理论,构建损伤演化方程和损伤场与应力应变场的耦合方程,使用损伤力学-有限元方法进行联合仿真,得出活塞疲劳损伤的演化规律呈指数型增长,预估出活塞的疲劳裂纹萌生寿命,给实际生产的活塞设计、制造及热处理工艺等提供了一定的指导,并为评估冲击类构件的疲劳寿命提供了新的分析思路。The damage mechanics finite element method is used to simulate the fatigue crack initiation life of im- pact piston. The dynamic analysis of the impact system is carried out by using Ansys software, and the stress and strain variation law of the piston during the impact collision is obtained and the position of the dangerous point is de- termined as the end of the piston, then the stress and strain response of the dangerous point is extracted, with material S-N curve and the theory of damage mechanics, the damage evolution equation and the coupling equation of damage field and stress strain field are constructed, using damage mechanics finite element method, it is concluded that the evolution law of piston fatigue damage is exponential growth. The fatigue crack initiation life of the piston is esti- mated, and some guidances for the actual production of the piston design and manufacture and heat treatment process are provided, and a new analysis method for fatigue life assessment of impact components is proposed.

关 键 词：活塞 疲劳 损伤力学 萌生寿命 

分 类 号：TP391.9[自动化与计算机技术—计算机应用技术]