Expansion of the solar wind from a two-hole corona

A one-fluid model is employed to study the global expansion of the solar wind from a two-hole corona, under the assumptions that the holes are confined to polar caps within 30 deg of heliographic colatitude, the flow is steady and axisymmetric, and the geometry of streamlines is prescribed. The boundary conditions are adjusted in such a way that the calculated solar-wind properties at 1 AU are in reasonable agreement with observational results. A series of numerical solutions are obtained, the series produces a maximum terminal speed of 829 km/s at the pole. The calculated solar-wind speeds are strongly latitude-dependent and are positively correlated with local divergence factor of a stream tube. The solutions imply that most plasma properties are highly inhomogeneous at the polar caps. The flow velocity, the temperature, the proton-number flux and the conduction-heat flux all increase towards the hole center.