Research On Multipole Field Reconnection Electromagnetic Launcher

Electromagnetic launch technology is an excellent emission method.Its principle is based on the interaction between the magnetic field and eddy current effect,which uses the electromagnetic force to push the emitter to reach the target speed.The main advantage of electromagnetic launch technology is that the emission efficiency is high,and the speed of the emitter is not subject to the speed of sound and has the potential to push large mass objects,so it has attracted much attention.It has good application prospects in various fields such as transportation,aerospace and military weapons.Electromagnetic guns have the following three types,rail guns,coil guns and reconnection guns.Coil guns and rail guns have long history of research.The former problem is that the axial force of the acceleration emitter is smaller than the radial force,and the latter has the problem of sliding electrical contact.These principled deficiencies are still difficult to overcome.The research history of reconnection guns is relatively short.Although the above problems do not exist,the mass of the emitter is small,which limited its application.Based on the basic principle of the plate-shaped projectile reconnection guns,and the multipole configuration,a new launch mode called multipole field reconnection electromagnetic launcher are proposed.This configuration can solve the above problems.As a relatively new configuration,many mechanisms need to be further explored.The new configuration proposed in this paper is based on the plate-shaped projectile and Pie drive coils reconnection guns.Therefore,the basic principle and circuit equation of the reconnection guns will be introduced first,which will provide a theoretical basis for exploring the law of the new configuration.Then the electromagnetic field equations of the reconnection guns are introduced,which are the magnetic field distribution of the driving coil and the eddy current distribution induced by the emitter.With theoretical derivation,the static magnetic field simulation is performed by the finite element simulation software Ansys Maxwell to observe the magnetic field distribution.The same model is used for transient field simulation,and the transmission performance of the reconnection guns is analyzed based on the speed curve,force curve and current curve obtained from the simulation results.After introducing the basic theory of reconnection guns,the multipole field reconnection electromagnetic launch mode is proposed,the basic principle of this configuration emission is introduced,and the mathematical model of multipole moment configuration is introduced.Static magnetic field simulation of the model shows that there is coupling between adjacent drive coils,which will strengthen the magnetic field at the drive coil diameter,which is beneficial to the reconnection of magnetic lines.The transient field simulation shows that this configuration can accelerate the 0.49 kg projectile armature at the speed of 0 to 658.3m/s,and observe that the force of the projectile armature is large and the radial force is small.The energy conversion efficiency is 21.23%,which indicates that the launch mode has the potential of high-speed emission,large thrust,suspension characteristics,high efficiency and the like.It is a configuration with excellent launch performance.Then the effects of capacitor parameters on the emission performance and the optimal design of the drive coil were studied.Through simulation,it is found that after one parameter is determined for the voltage value and the capacitance value of the capacitor,the outlet speed increases as the other parameter increases,and the energy conversion efficiency first increases and then decreases.For the simulation of the drive coil structure parameters,it is found that the increase of the length and the number of turns of the drive coil will reduce the launch speed,and the length and the number of turns should be set reasonably.In addition,the driving coil of the trapezoidal structure is proposed.Through the comparison of the simulation results,it is found that the emission system of the trapezoidal structure coils has better emission performance,which provides an idea for the structural design of the driving coils.Finally,a simulation model of three-level launch is built,and a method for determining the optimal trigger position of multi-stage launch is proposed.And the multi-stage emission level coupling relationship is analyzed.