Simulation And Experimental Researches On The Three-stage Reconnection Electromagnetic Launch System

In the field of launch weapons, there are some unsurmountable limits in velocity and cost for the traditional launch technologies using chemical energy. Thus, it's a great improvement to apply electromagnetic energy in the launch technology. Among several forms of electromagnetic launch, reconnection electromagnetic launch is a newly developed one. It can not only overcome the disadvantages of severe erosion in rail electromagnetic launch and complex synchronization in coaxial coil electromagnetic launch, but also potentially combine the advantages of achieving hypervelocity in rail electromagnetic launch and launching large mass in coaxial coil electromagnetic launch. Therefore reconnection electromagnetic launch is regarded as a form of electromagnetic launch with good perspective and wide use.This dissertation takes the multi-stage reconnection electromagnetic launch with flat plate projectile and box-shaped drive coil as the studying object. The synthesized equations on the drive coil electromagnetic field and the projectile eddy current are analyzed and deduced. By means of the ANSOFT software for electromagnetic field finite element analysis, a new three-dimensional finite element simulation model of multi-stage reconnection electromagnetic launch is established. The multi-stage drive coil electromagnetic field distribution and the projectile eddy current distribution are simulated and computed. With the Virtual Work method, motion equations on multi-stage reconnection electromagnetic launch under hypervelocity circumstance are deduced, and the weighted coefficients of fore-stage drive coils are put forward to reflect the influence of the current frequency or phase difference of various coils. The motion equations show that the force on the projectile within a certain drive coil is a synthesized result of the certain drive coil and the fore-stage drive coils considering the influence of the current frequency and phase differences.A numeric integral simulation model of the motion course of reconnection electromagnetic launch is established with four-order Runge-Kutta method. Combined with parameters of the actual electromagnetic launch experimental system, numeric simulation of multi-stage reconnection electromagnetic launch course is carried out. The influences of initial projectile position, resistance of the discharge circuit, input power energy, and stages of launch are also discussed. This work applies triggered vacuum switch (TVS) for the circuit making in reconnection electromagnetic launch, and analyzes the feasibility to improve the launch efficiency for the remained energy in capacitor banks caused by the arc extinguishing...