IDIT   25587
INSTITUTO DE ESTUDIOS AVANZADOS EN INGENIERIA Y TECNOLOGIA
Unidad Ejecutora - UE
artículos
Título:
Characteristic boundary conditions for magnetohydrodynamics: The Brio?Wu shock tube
Autor/es:
KRAUSE, G. J. ; CIMINO, A. M; ELASKAR, S. A.; COSTA, A
Revista:
COMPUTERS & FLUIDS
Editorial:
PERGAMON-ELSEVIER SCIENCE LTD
Referencias:
Lugar: Amsterdam; Año: 2016 vol. 127 p. 194 - 210
ISSN:
0045-7930
Resumen:
In the present paper we develop and test a characteristic-based boundary condition (BC) scheme for the compressible magnetohydrodynamic equations, as the extension of a characteristic gasdynamics BC model. We use a Harten?Yee finite volume scheme for the spatial discretization of the domain, and a TVD Backward Euler time integrator for the sake of robustness. First we verify that the scheme works correctly for gasdynamic initial conditions (i.e., when B = 0), comparing with both analytical and experimental data. We then test the BC scheme with the Brio and Wu shock tube for two different types of boundaries: an open end and solid walls. We present a comparison between results obtained with the zeroth-order extrapolated BC scheme and the characteristic scheme developed. For a solid wall condition, we found discrepancies between both schemes when perturbations in the transverse magnetic field component (B y ) reach the boundaries. Also for the open end condition some discrepancies appear between the characteristic and extrapolated schemes, presenting the latter some instabilities. The results obtained with the characteristic scheme are smoother but presented a different wave pattern, which we believe is physical.