FINITE VOLUME SIMULATION OF SOLAR DARK LANES STRUCTURES

ELASKAR, SERGIO; COSTA, ANDREA; SCHULZ, WALKIRIA; CID, GUILLERMO

Buenos Aires

Congreso; CILAMCE 2010 (XXXI Iberian-Latin-American Congress on Computational Methods in Engineering) and MECOM 2010 (IX Argentine Congress on Computational Mechanics and II South American Congress on Computational Mechanics).; 2010

Asociación Argentina de Mecánica Computacional y UBA

We integrate the ideal magnetogasdynamics equations to simulate dark void sunwardmoving structures in post-flare supra-arcades. We study the generation and evolution of the internalplasma instability to compare with observations and to gain insight into physical processes andcharacteristic 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 cannumerically 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.