A New Electro-Thermal Simulation Approach for Moving Electromagnetic Rail Launchers

In recent years, the electromagnetic rail launcher (ERL) technology has garnered widespread attention in the field of launch systems due to its outstanding performance. During ERL system operation, a large pulsed electric current flows through the system, sharply accelerating the armature to a high speed within an extremely short period, accompanied by a rapid temperature increment. This process involves complex multi-physical phenomena, posing challenges to the design and simulation of ERL systems. We propose a dynamic simulation solution for the ERL launch process through an electromagnetic-thermal-kinematics cycle. In the electric-thermal coupling simulation, the temperature-dependent electrical conductivity is considered. Joule heat produced by current is employed as the heat source for the temperature field, enhancing the accuracy of the thermal simulation. In the electromagnetic-kinematics cycle, integrating the Lorentz force acting on the armature directly simulates the force situation of the ERL propulsion. Based on the designed dynamic simulation process for the multi-physics fields of ERL systems, the accuracy of the proposed method has been validated through simulations involving square and C-type armature ERL systems, as well as laboratory measurements. Unrestricted by the limitations of control equations and solution processes, the proposed method enables flexible simulation of ERL systems.