Dynamics of quasi-spherical Z-pinch implosions with mass redistribution and displacement modification

Abstract

Implosions of (quasi-)spherical loads with mass redistribution and displacement modification are investigated numerically. Both methods can theoretically counterbalance the nonuniformity of magnetic pressure along the load surface and realize quasi-spherical Z-pinch implosions. Mass redistribution is feasible for spherical loads with large radius and weight, while the displacement modification is more suitable for light loads, such as those composed of wire arrays. Simulation results suggest that, for mass redistributed spherical loads, wall instabilities induced by polar mass flows will deform the imploding shell. For prolate spherical loads, in which the wall instability cannot develop, the kinetic energy distribution is disturbed at high latitude. These passive behaviors and their possible mitigation methods, such as reshaping the electrode, are investigated numerically in this paper.

Theoretical and numerical research of wire array Z-pinch and dynamic hohlraum at IAPCM

“…Another issue to be discussed for the QSDH design is the shape of the foam target. Since the inherent non-uniform kinetic energy E k of quasi-spherical implosions increases with the latitude [93], which results in uneven shock propagation in the foam target, ellipsoidal foam M A N U S C R I P T…”

“…Previous attempts on the Angara5-I [87] and MAGPIE generators did not show compelling evidence of QS implosions with wire-arrays. As a solution to the abovementioned problem, we developed a new method of getting QS implosions with wire-arrays, in which the mass-redistribution is replaced by a shapemodification [93]. Fig.…”

A vertex‐centered linearity‐preserving discretization of diffusion problems on polygonal meshes

“…Anisotropic diffusion problem of this type arises in a wide range of scientific fields such as oil reservoir simulations, plasma physics, and semiconductor modeling. Here, we are concerned with the simulation of 2D Z‐pinch driven inertial confinement fusion where a certain magnetic diffusion process is coupled with radiation hydrodynamics and the accurate evaluation of magnetic field at cell vertices is required. In accurate simulation of diffusion processes in these applications, finite volume (FV) method is among the most commonly used ones because of its simplicity, local conservation, and some other good numerical properties.…”

Recent advances in theoretical and numerical studies of wire array Z-pinch in the IAPCM

“…The conventional method to obtain quasi-spherical (QS) implosion is to modulate the load mass distribution along the axis, which is not feasible for wire-arrays. We developed a new method of displacement modification to obtain QS implosion [9] , as shown in Fig. 9.…”