Multi-parameters study on underwater coil launch

Abstract The projectile launched by electromagnetic weapon has strong kinetic energy. In order to study the laws and characteristics of electromagnetic induction coilgun launching underwater, a multi-stage coilgun model was established in this paper. Based on the control variates method, the effects of trigger position, coil turns, capacitance value and other parameters on the launching process were studied, then the effects of above factors on the launching efficiency and exit speed were analyzed. The results show that the optimal trigger position offsets to the direction of the breech with the increase of the projectile speed; the optimal coil turns for a certain projectile and launching occurs when the trigger position is determined; the increase of the capacitance value can increase the exit speed of projectile, and the capacitance value should be selected according to the efficiency-speed curve when the launch efficiency is considered; the seawater resistance has little influence on the acceleration of the projectile, and comparatively large influence when there is no driving force. The research results of this paper can provide theoretical support for the manufacture of underwater coilgun prototype.