随机载荷作用下自行火炮扭カ轴疲劳可靠性分析与仿真

建立了自行火炮虚拟样机，仿真获得了各典型工况下扭力轴的扭矩载荷时间历程。通过有限元分析、计数统计和合成扩展，获得了扭力轴花键根部最危险部位的全寿命里程二维疲劳应力设计谱。考虑了几何尺寸和疲劳强度影响因素的随机性，利用Monte-Carlo抽样和3-6-1 BP网络仿真了疲劳横向应力的概率密度函数，并获得了扭力轴的p-Sa-Sm-N曲面方程。研究了疲劳横向随机性和纵向随机性的本质区别和计算方法，结合修正二维概率(MTP) Miner准则理论，对扭力轴进行了疲劳可靠性分析。建议扭力轴的大修周期为12 000 km.

Fatigue Reliability Analysis and Simulation of Self-propelled Gun''''s Torsion Bar Under Random Loads

Virtual prototype for a self-propelled gun was built up and simulated to obtain the torque load of the torsion bar under various typical conditions.The design spectrum of the full life 2D fatigue stresses at the most dangerous fatigue failure position located in the root of spline tooth of torsion bar was obtained by finite element analysis,counting and evaluating,composing and extending.Considering the randomness of the geometrical sizes and fatigue strength effect factors,we simulated the probability density function of fatigue transverse stresses by Monte-Carlo sampling theory and 3-6-1 BP neural network,and obtained the p-Sa-Sm-N curved surface equations.The essential difference between transverse and longitudinal randomnesses of fatigue and their computation methods were studied,and the fatigue reliability of torsion bar was analyzed by MTP Miner criterion theory.It is suggested that the mean kilometers between overhauls is 12 000 km.