A Numerical Path-preserving and Path-conservative Osher–Solomon Scheme for Solar Wind Simulation

Abstract

We develop a numerical path-preserving and path-conservative Osher–Solomon scheme (NPP-POS) for steady-state solar-wind simulations within the ideal GLM-MHD framework. The method evaluates the Osher–Solomon interface dissipation through a numerically integrated state-space path and incorporates a numerical path-preserving correction designed to mitigate pseudoconvergence associated with spurious intermediate states and to improve the treatment of Alfvénic characteristics across tangential-field discontinuities. Controlled MHD Riemann tests show that NPP-POS better preserves large-angle tangential-field rotations and suppresses spurious intermediate structures compared with the original POS scheme. In the CR 2193 background solar-wind simulation, POS and NPP-POS produce broadly similar large-scale magnetic structures. HCS-focused diagnostics suggest that NPP-POS can reduce local residuals, sharpen the magnetic reversal layer, and decrease the estimated heliospheric-current-sheet thickness. The CR 2193 solution reproduces the main coronal and near-Sun solar-wind features and is broadly consistent with near-Sun remote-sensing constraints and in situ solar-wind measurements after ballistic mapping. Overall, the results suggest that NPP-POS improves the numerical treatment of tangential-field reversal regions while retaining the practical capability required for global solar-wind modeling.