A GLOBAL 3-D SIMULATION OF INTERPLANETARY DYNAMICS IN JUNE 1991

The global dynamics of the solar wind and interplanetary magnetic fiel d in June 1991 is simulated based on a fully three-dimensional, time-d ependent numerical MHD model. The numerical simulation includes eight transient disturbances associated with the major solar flares of June 1991. The unique features of the present simulation are: (i) the distu rbances are originated at the coronal base (1 R(s)) and their propagat ion through inhomogeneous ambient solar wind is simulated out to 1.5 A U; (ii) as a background for the transients, the global steady-state so lar wind structure inferred from the 3-D steady-state model (Usmanov, 1993c) is used. The parameters of the initial pulses are prescribed in terms of the near-Sun shock velocities (as inferred from the metric T ype II radio burst observations) relative to the preshock steady-state flow parameters at the flare sites. The computed parameters at the Ea rth's location for the period 1-18 June, 1991 are compared with the av ailable observations of the interplanetary magnetic field, solar wind velocity, density, and with variation of the geomagnetic activity K-p index.