The concept of Distributively Induced Quasi-Spherical Implosion Fusion (DIQSIF) and an analytic model for evaluating MRT instability within it

The key constraint and bottleneck of dynamic magnetic pinch inertial fusion is MRT instability. This instability can be significantly suppressed by employing a directionally time-varying (rotating) driving magnetic field [1–4]. On the basis of this concept, it is possible to further utilize axial distributively induced currents to realize quasi-spherical implosion for direct compression of target pellet to achieve inertial fusion (DIQSIF) [5], significantly improving dynamic stability while increasing compression and closing endface losses. To evaluate the MRT instability in the DIQSIF configuration, we propose an analytic model to describe the implosion dynamics, instability development, and driver-load coupling. The model is applicable to quasi-spherical implosions, organically unifying cylindrical implosions and spherical implosions. In the part of instability, not only the effect of the direction of the driving magnetic field changing (rotating) over time, but also the finite thickness effect and the radial convergence effect (BellPlesset effect) of the imploding shell are taken into account.