Three-dimensional MHD modeling of the solar wind in the outer heliosphere

Arcadi V. Usmanov, Melvyn L. Goldstein, and William H. Matthaeus

We have developed a fully three-dimensional magnetohydrodynamic solar wind model that takes into account turbulent heating by in situ velocity and magnetic fluctuations as well as heating and other effects produced by interstellar pickup protons treated in the model as a separate fluid. The model is based on the Reynolds decomposition of the flow and magnetic field into mean and fluctuating quantities. The model equations describe the solar wind plasma in the rotating frame of reference and include heating by turbulent dissipation, energy transfer from interstellar pickup protons to solar wind protons, and solar wind deceleration due to charge exchange and/or photoionization with interstellar hydrogen. The model is used to simulate the global steady-state structure of the solar wind in the region from 0.3 to 100 AU. We will present the simulation results for a source field on the Sun that is either a dipole (aligned or tilted with respect to the solar rotation axis) or is inferred from solar magnetograms.