SOLVING THE NAVIER-STOKES SYSTEMS WITH WEAK VISCOSITY AND STRONG HEAT-CONDUCTION USING THE FLUX-CORRECTED TRANSPORT TECHNIQUE AND THE ALTERNATING-DIRECTIONAL EXPLICIT METHOD

The flux-corrected transport (FCT) technique and the alternating-direc tion explicit (ADE) method are coupled through a time-splitting techni que. This new combination of both methods has been used successfully t o solve the fully coupled Navier-Stokes system applied to ionospheric thermal plasma flows with a viscosity and strong heat conduction. The combined scheme gives convergent solutions within the time step set fo r nonlinear stability of the corresponding nondissipative flow fields, and the time-dependent solutions are consistent with other model resu lts using different methods. To have a quantitative view of the Aux-li miter of Boris' FCT version, a concept of local variation is defined t o identify local extrema. The total variation diminishing scheme finds unique entropy solutions for vanishing dissipation. The ADE scheme, h owever, enables us to handle dissipation when the FCT technique alone can be inappropriate. (C) 1998 Academic Press.