1. Aerospace College, Nanjing University of Aeronautics and Astronautics ,Nanjing 210016 China；
2. School of Transportation and Vehicle Engineering, Shandong University of Technology, Zibo 255049 China
A Vibration fatigue life prediction method of the structure under multi-axial random excitation
A frequency domain method for fatigue life prediction of the structure under multi-axial random excitation is presented. Fristly, the matrix of the transfer function from excitation acceleration to the response stresses is obtained through frequency response analysis. According to the random vibration theory, the PSD matrix of stress response is calculated. Secondly, the multi-axial stress problem is translated to the uniaxial stress problem via equivalent Von Mises stress PSD. Finally, the uniaxial frequency domain fatigue analysis is used for the fatigue life prediction. The fatigue life of a typical component under the multi-axial random excitation is calculated and compared with the test result . In addition, the fatigue damages of the component caused by the simultaneous multi-axial and uniaxial excitation are analyzed and compared and the multi-axial effect is also analyzed. The result shows the necessity of simultaneous multi-axial fatigue research.
1. Aerospace College, Nanjing University of Aeronautics and Astronautics ,Nanjing 210016 China；
2. School of Transportation and Vehicle Engineering, Shandong University of Technology, Zibo 255049 China
A frequency domain method for fatigue life prediction of the structure under multi-axial random excitation is presented. Fristly, the matrix of the transfer function from excitation acceleration to the response stresses is obtained through frequency response analysis. According to the random vibration theory, the PSD matrix of stress response is calculated. Secondly, the multi-axial stress problem is translated to the uniaxial stress problem via equivalent Von Mises stress PSD. Finally, the uniaxial frequency domain fatigue analysis is used for the fatigue life prediction. The fatigue life of a typical component under the multi-axial random excitation is calculated and compared with the test result . In addition, the fatigue damages of the component caused by the simultaneous multi-axial and uniaxial excitation are analyzed and compared and the multi-axial effect is also analyzed. The result shows the necessity of simultaneous multi-axial fatigue research.
贺光宗 1,2,陈怀海1， 贺旭东1. 一种多轴向随机激励下结构疲劳寿命分析方法[J]. 振动与冲击, 2015, 34(7): 59-63.
He Guangzong 1,2 Chen Huaihai 1,HE Xu-dong1. A Vibration fatigue life prediction method of the structure under multi-axial random excitation. JOURNAL OF VIBRATION AND SHOCK, 2015, 34(7): 59-63.
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