Investigation on the Spatial-Temporal Distribution of Electromagnetic Gun Rail Temperature in Single and Continuous Launch Modes

In order to study the spatial-temporal distribution characteristics of electromagnetic rail gun temperature, based on moving grid processing method and mod function method, a 3-D geometric model of electromagnetic rail gun under single launch mode, a 2-D geometric model of electromagnetic rail gun under continuous-fire mode, and the corresponding transient electromagnetic field-temperature field coupling model are established by using the finite element analysis software COMSOL Multiphysics, and the temperature spatial-temporal distribution characteristics in the rail-armature contact area, cross section of rail, and along the rail axis is simulated under single launch and continuous launch. The results show that, under the conditions of single launch and natural cooling, the high temperature area in the rail-armature contact surface is located at the rear of the armature due to the skin effect. The temperature distribution along the axial inner side of rail tends to be higher near the tail and lower near the muzzle, it increases with time, but the peak temperature does not exceed the melting point of copper. Under the continuous launch and natural cooling, after five launches, the peak temperature of the rail increases to 709 °C, which is close to the melting point of copper. Continued launching will cause rapid accumulation of heat in the rail and a rapid increase of peak temperature, resulting in shortened life of the launcher and even launch failure. Therefore, without active cooling measures, the electromagnetic rail gun cannot be used in actual combat. The results of the study are an important guide for the design and thermal management of the cooling system of electromagnetic rail gun.