Modelling of the conductor vaporization process for single-turn coil

Single-turn coil (STC) is a destructive pulsed magnet aiming at 100–300 T ultra high magnetic field. A conductor vaporization model is proposed for STCs. Using this model, the vaporization characteristics at different inner diameters and discharge currents are investigated. The results show that vaporization always starts from the inner surface of the conductor, but only from the interior of the conductor at higher current and smaller inner diameter. Moreover, the vaporization causes the electrical conductivity to decrease, leading the area with the highest current density to advance to the interior of the conductor. By comparison, the vaporization start time decreases as the current increases and the inner diameter decreases, and the vaporization start time at different diameters tends to coincide as current increases. The model in this study is validated by checking the consistency of the magnetic flux density at the central axis of STCs of the simulation results and the experimental data.