Dynamics of cylindrical conducting shells in a pulsed longitudinal magnetic field

Abstract

A theoretical model is constructed for describing the motion of a cylindrical conducting shell in a pulsed longitudinal magnetic field generated by an external solenoid. The model takes into account the dynamics of the electric circuit (with the solenoid as its part), inertial and strength properties of the shell, magnetic field diffusion, and heating of the solenoid and shell materials. Difference schemes are constructed for the numerical solution of the system of the defining differential equations, and the criteria of their stability are analyzed. The model is used for studying magnetic-p ulse compression of hollow shells, as well as magnetic field compression in their inner cavity, and the effect of controlling parameters such as the starting charge voltage of the energy storage system and the size of the shell being compressed on the process dynamics is analyzed. Various approximations for calculating the shell heating (adiabatic approximation and uniform heating approximation) are analyzed in comparison with rigorous calculations. The possibility of conducting shell expansion due to magnetic field diffusion into the inner cavity is investigated.