Equation of the state and destruction analysis for single-turn coil in light of high pressure and Mega-Gauss magnetic field

Single-turn coil (STC) is a destructive pulsed magnet aiming at 100-300 T magnetic field. Predicting the coil destruction time is important for STC because the magnetic energy density should be maximized before the coil expansion as well as the destruction becomes significant. In this study, a conductor damage accumulation model is proposed to analyse the damage accumulation process of STC, and derive the equation of state under high pressure and Mega-Gauss magnetic field. This model also gives the approach to realise the coupling between the solid-liquid phase transition caused by dramatic temperature rise, and conductor damage caused by high electromagnetic force. The results show that the conductor damage always starts to occur from the inside of the conductor near the edges of the inner surface but still at some distance from these edges, because the negative tension pressure of this region is the highest during discharge. If the conductor damage is ignored, the negative pressure of the conductor calculated from the simulation can be very high and unreasonable. By comparison with experimental data, the error of the magnetic field simulation is the smallest when solid-liquid phase transition, shock deformation, and damage accumulation are all taken into account.