ud-Doula and Owocki (2001) have performed MHD simulations of magnetically channelled winds: Equatorward flow inside closed field lines and associated strong shocks are seen.
y-component of velocity
The large x-ray luminosities and hard x-ray spectra (of q1 Ori C  and t Sco) already argue against instability-generated shocksÉ
Éand suggest that a hybrid wind-magnetic model might be appropriate, especially on q1 Ori C, on which an 1100 G dipole field has been discovered