变压吸附器疲劳裂纹扩展剩余寿命的研究

Research on Fatigue Crack Propagation Residual Life of Pressure Swing Adsorption

针对承受周期性疲劳载荷的一种压力容器——变压吸附器,对其疲劳裂纹扩展剩余寿命进行预测。基于断裂力学,求出裂纹初始深度和临界深度。利用ABAQUS中的扩展有限元功能确定变压吸附器裂纹萌生的位置,并得到裂纹深度a与应力强度因子幅ΔK的关系式,利用Pairs公式得到裂纹扩展寿命。结果表明:计算得到裂纹初始深度为0.9 mm,临界深度为12.9 mm。将ABAQUS仿真得到的裂纹深度和应力强度因子幅数据进行拟合,可得到两者的关系表达式。将该关系表达式及其它相关参数带入到Pairs公式,得到裂纹从初始深度扩展到临界破坏深度对应的设备剩余工作年限为1.3年。该评估结果为变压吸附器安全运行提供了理论上的支撑。

Aiming at pressure swing adsorption, a kind of pressure vessel exposed to periodic fatigue load, the residual fatigue crack propagation life of the pressure swing adsorption was predicted. Based on fracture mechanics, the initial depth and critical depth of the crack were obtained. The cracking initiation location of the pressure swing adsorption was determined by extended finite element method in ABAQUS, and the relation equation between crack length and stress intensity factor range was obtained, then the crack growth life was predicted by using Paris formula. The results show that by calculation, the crack initial depth is 0.9 mm,the crack critical depth is 12.9 mm. The crack depth and stress intensity factor range obtained by ABAQUS are fitted, and then the relation equation of the data above is obtained. By bringing the relation equation and other relevant parameters into Paris formula, the residual working life of the equipment relating to the fatigue crack propagation from initial depth to critical failure depth is obtained, which is 1.3 years. Thus, the assessment results can provide theoretical support for safety work of pressure swing adsorption.