PARAMETRIC STUDY OF INTERACTION EFFECTS OF FAST AND SLOW CO-ROTATING SOLAR-WIND STREAMS

Through numerical calculations, a study is made of the influence of ma in plasma and magnetic field characteristics, and of the solar wind (S W) inhomogeneity near the Sun upon the effectiveness of interaction of fast and slow SW streams in interplanetary space. A two-dimensional, two-fluid magnetohydrodynamical SW model with the inclusion of Alfven waves was used. The study has revealed a group of parameters that have a substantial effect on solar wind characteristics in the region of i nteraction of its fast and slow streams. Alfven waves have been found to influence the effectiveness of interaction of such streams. In term s of the model used in the parametric investigation of the interaction of co-rotating streams, it was also possible to obtain new results co ncerning the SW acceleration characteristics in a 2-D approximation. O n this basis we suggest the idea of a likely physical mechanism that g overns the velocity of SW outflow from coronal holes, depending on the ir size.