NUMERICAL RESEARCH ABOUT WHITE LIGHT CORONAGRAPH FIGURE OBSERVED AT MAY 2 1998

A new model of 2-D ideal magnetohydrodynamic equations, which sets spherical coordinates （γ, φ） on the plane of sky to avoid singular geometry at solar poles, is employed to simulate white light coronagraph figure. Numerical white light figure of the final self-consistent steady state, calculated with initial magnetic field constructed from a magnetic hexapole and several dipoles and with projected characteristic inner boundary condition, agrees basically with the observed coronagraph figure. The simulation also shows that magnetic structure dominates the solar wind flow field.