A Modeling and Measuring Method for Armature Muzzle Velocity Based on Railgun Current

In this article, the circuit model and the dynamic model of railgun launching process are established by analyzing the Lorentz force, air resistance, and friction force of the armature in the gun bore. Based on the armature dynamic model, a muzzle velocity model of armature can be simulated by utilizing MATLAB, which takes the launching current and loading force of railgun as the main input parameters. Through those two input parameters, the variation curve of armature velocity is measured and calculated by using the armature muzzle velocity model. Moreover, we can read the armature muzzle velocity from the armature variation curve. The influencing factors of the muzzle velocity of armature in this model are also calculated and analyzed, respectively. Comparing with the armature muzzle velocity measured by net target and B-probe, the result shows that the armature muzzle velocity model can accurately estimate the armature muzzle velocity, and can be used to calculate the muzzle velocity in the railgun launching experiment. This method provides reference for the performance optimization design of railgun.