A 2.5-dimensional MHD Alfvén-wave-driven solar wind model

A 2.5-dimensional MHD analysis of Alfvén-wave-driven solar wind in the heliospheric meridional plane is presented in order to extend the one-dimensional model proposed by Weber and Davis [1967] to the two-dimensional case. In our model, no energy input is applied to the helmet streamer, while the solar wind along open field lines is assumed to be driven by Alfvén waves. The differential rotation of the Sun is considered. The numerical results obtained essentially match relevant Ulysses observations and give the spatial distribution of the azimuthal components of the flow velocity and magnetic field. The effect of the existence of these azimuthal components on the global properties of the solar wind is found to be negligible, and the loss rate of the angular momentum of the Sun due to the solar wind is estimated.