单轨火箭橇在轨动力特性数值分析

Numerical analysis of dynamic characteristics of monorail rocket sled on rail

为系统性分析火箭橇在轨动力特性,采用三维Eluer-Bernouli梁单元对火箭橇系统进行离散,通过重构生成长程不平顺轨建立考虑轨道不平顺及滑靴磨损的靴轨非线性接触力模型,由Newmark-β结合Newton-Raphson局部迭代求解非线性动力学方程获得火箭橇在轨动力特性数值解,并通过试验验证,计算结果表明:马赫数为2的速度下火箭橇质心竖向过载峰值约为2 700g;火箭橇在轨占空比与航向速度成正比,马赫数为2的速度下竖向火箭橇在轨占空比为16%;高速段滑靴磨损量占全弹道磨损量的84%,靴轨单次接触磨损量与航向速度3次方成正比。

To systematically analyze the dynamic characteristics of rocket sled travelling along rail,the three-dimensional Eluer-Bernouli beam elements were used to discretize the rocket sled system,and the nonlinear contact force model of the slipper-rail considering rail irregularity and slipper wear was established by reconstructing the long-range irregularity rail,and finally,the nonlinear dynamics equations was solved by Newmark-β combined with Newton-Raphson local iteration method to obtain the numerical solution of dynamic characteristics on rocket sled.Though experimental verification,the results showed that the peak value of the vertical overload to the mass of rocket sled was about 2 700g at Mach number of 2 speed;the duty cycle of rocket sled on rail was proportional to forward speed,and the vertical duty cycle of rocket sled was 16%at Mach number of 2 speed;the wear of slippers in high speed section accounted for 84% of the total trajectory wear,and the single contact wear of slipper-rail was proportional to the third power of the forward speed.