Analysis of Vibration Characteristics of Augmented Electromagnetic Railgun

In order to study the vibration characteristics of the enhanced electromagnetic railgun, a full model of barrel vibration coupled with electrical, magnetic and structural Multiphysics simulation was established based on the LS-DYNA platform. Combined with theoretical analysis and experimental research, the preliminary time-frequency characteristics of barrel vibration signals were obtained. The theoretical analysis shows that the frequency component of the barrel vibration signal is mainly related to the excitation frequency, and the excitation includes the electromagnetic repulsion force between the rails and the impact of the armature on the rails (that is, the armature-rail contact force). The experiment shows that the trend of vibration signals at a certain position of the barrel in the time domain is related to the position of the armature. Before and after the armature passes through this position, the amplitude of barrel vibration is relatively slow, mainly caused by electromagnetic repulsion between the rails; When the armature passes through this position, the vibration amplitude of the barrel is relatively large, mainly caused by the impact of the armature on the barrel. In frequency domain, the vibration frequency band caused by electromagnetic repulsion force is lower, and the vibration frequency band caused by armature-rail contact force is higher. The trend obtained from the simulation results is basically consistent with the experiment, and based on further analysis of the simulation, the impact force on the barrel will slowly increase in the time domain after the armature is activated. As it approaches the muzzle, the impact force will slowly decrease, while in the frequency domain, it shows an increasingly concentrated trend in the high-frequency band.