PPPS-2013: Multi-physics coupling field analysis of the electromagnetic rail-gun barrel

The electromagnetic rail-gun is a kind of high-energy device which uses a high-current electrical pulse to accelerate projectiles to hypersonic velocity, and the launch performance of the system is affected by the thermal characteristic during the launching process1. The electromagnetic rail-gun system is a multi-physics coupling field system2, so the different aspects and their interaction of the system should be considered when we analyze the performance of the barrel during the launching process. In this research, utilized finite element method to simulate the process that the armature squeezes the barrel, and the three-dimension finite element model of the barrel and the armature were established in the finite element analysis software ANSYS. The finite element models for eddy current heat, Joule heat and friction heat are established to simulate the transient thermal distribution, and the temperature distribution characteristic was analyzed. The magnetism-structure directly coupling analysis and the magnetism-thermal-structure analysis of the barrel were accomplished. Based on the analysis above, the stress and strain distribution, the magnetic field distribution and temperature distribution were obtained. Comparing the results of the two kinds of analyses above, how load distribution influences the displacement and the stress of the electromagnetic rail-gun, structure deformation influence the magnetic field and temperature field influence the structure were acquired. Finally, the research analysed the effect of the intensity and stiffness of the barrel under different current intensity, and the maximum current intensity that the rail can sustain with specified materials and structure was obtained, which has a reference value for further research.