The vibration reduction optimization of the body tube fastening of EM rail launcher

Abstract

In order to further optimize the vibration reduction effect of the body tube fastening of the electromagnetic rail launcher, the vibration reduction optimization scheme of the body tube fastening is determined by the modal superposition method. The electromagnetic rail launcher is simplified to Bernoulli-Euler beam, the vibration equation of the rail is established, and the inherent characteristics of the rail are analyzed. The multi-field coupled finite element model of the electromagnetic rail launcher is established and the complete transient launching process of the launcher is simulated. Based on the modal analysis of the system stiffness at the critical velocity, the optimal position of the tube fastening is determined, and the influence of different fastening positions on the damping effect is analyzed. The results show that the fastening of the body tube can effectively improve the structural stiffness of the electromagnetic rail launcher, and the damping effect of the fastening is affected by the vibration characteristics of the fastening position. The addition of fastening leads to the stress concentration in the adjacent part of the rail, which increases the requirement of rail strength. When the fastening is set in the front part of the rail, the vibration reduction effect is obvious. When it is set in the back part, the resonance range of the critical velocity should be avoided and the priority should be given to the position before the critical velocity.