A two region model of the solar wind including azimuthal velocity.
Abstract
The tworegion model of the solar wind divides the interplanetary space into two regions: it assumes that the solar wind is onefluid in an inner region within 0.4 AU and twofluid in an outer region beyond 0.4 AU. This paper includes the angular motion of the solar wind in the tworegion model. The flow in the onefluid region is governed by the onefluid magnetohydrodynamic equations. The second and third moment equations of the Vlasov equation together with other conservation equations are used to describe the solarwind flow in the twofluid region. The predicted azimuthal velocity at 1 AU is less than 2 km/s. All other macroscopic and microscopic properties from this model are in good agreement with experimental quiettime observations at 1 AU. The numerical results also confirm that when the azimuthal velocity is included in the analysis, the amount of magneticfield energy converted into kinetic energy in the solar wind is only a small fraction of the total expansion energy flux and has little effect upon the final radial expansion velocity.
 Publication:

The Astrophysical Journal
 Pub Date:
 February 1976
 DOI:
 10.1086/154134
 Bibcode:
 1976ApJ...203..720A
 Keywords:

 Astronomical Models;
 Interplanetary Medium;
 Solar Wind;
 Two Fluid Models;
 Azimuth;
 Magnetic Fields;
 Magnetohydrodynamic Flow;
 Mathematical Models;
 Numerical Analysis;
 Solar Wind Velocity;
 Vlasov Equations;
 Solar Physics