Finite Volume Simulation of Solar Dark Lanes Structures

Abstract

We integrate the ideal magnetogasdynamics equations to simulate dark void sunward moving structures in post-flare supra-arcades. We study the generation and evolution of the internal plasma instability to compare with observations and to gain insight into physical processes and characteristic parameters of these phenomena. The numerical approach uses a finite-volume method together the Harten–Yee total variation diminishing (TVD) scheme to integrate non-steady, onedimensional magnetogasdynamics. Two set of numerical tests were carried out, one of them in the sunward radial direction and the another one transverse to the sun’s magnetic field. We can numerically reproduce dark void solar observations. We show that the dark lanes are plasma vacuums generated by the bouncing and interfering of shocks and expansion waves produced by a localized deposition of energy. This energy deposition is modeled as a pressure perturbation. The pressure perturbation produces non-linear waves that compose the plasma void structures, with the same functional sunward decreasing phase speed and constancy with height of the period, as those determined by the observations.