2-D MHD Simulation of Two Axially Colliding FRCs Accelerated by Magnetic Pressure Gradient

Influences of Hall Effect on the Magnetohydrodynamic Behavior of Two Axially Colliding Field-Reversed Configurations

“…(4) is then zero by the vector identity, ∇ × ∇ξ = 0, where ξ is the arbitrary scalar function. Although the uniformity of the temperature gradually decreases, there is not much difference between the MHD results in [10] and the present Hall-MHD results.…”

“…Our previous resistive MHD model [10] does not take into account any toroidal magnetic field and was formulated under the assumptions of axial symmetry and nonflowing initial equilibrium. However, the inclusion of the Hall term results in the evolution of the toroidal magnetic field and flow.…”

“…In the translation experiments, a sequential change of the external field caused an axial acceleration of the FRC plasma. With respect to the temporal change of the external field, the computational model described in [10] is used herein in the same manner. According to this model, the mirror field region of the upstream side gradually approaches the FRC plasma.…”

“…2. The to-tal flux reads ψ t = ψ e + ψ p , where ψ e is the magnetic flux generated by the external coil current and ψ p is that generated by the plasma current and modified by the wall condition, see [10] for more details. It must be remarked that we defined ψ t ≥ 0 inside the separatrix.…”

“…In the present paper, we have reported the results from Hall-MHD simulations for FRC translation by a sequential external field control [10], axial collision between two accelerated FRCs, and a merging process. It has been found that a weak toroidal field is mainly generated during the translation phase.…”