Authors: Kan Liou(JHU/APL), Keiji Hayashi (GMU), Chin-Chun Wu (NRL), Brian Wood (NRL), James Chen (NRL, retired)

Title: Magnetohydrodynamic simulation of a flux rope coronal mass ejection: A new model

We have developed a magnetohydrodynamic (MHD) simulation model for studying the dynamics of coronal mass ejections (CMEs). This new model combines a semi-analytic flux rope model of Chen [1996] and an MHD coronal model of Hayashi [2005] and is capable of simulating CME events with a flux rope (or magnetic cloud events). The CME is initiated by inserting a static flux rope in the simulation domain near the surface of the Sun and released from the Sun by a pressure pulse. The geometry of the flux rope and the initial speed and direction are determined from the coronagraph observations by the SOHO/LASCO C2 and C3. The July 12, 2012 CME event is used to test the performance of the new model. The model CME is propagated to 1 AU using the MHD solar wind model of Wu et al. [2020]. The resulting flux-rope CME is compared with in situ measurements acquired by the Wind spacecraft. While a general good agreement is achieved, some improvements need to be done. We will present the detail result and discuss what needs to be done for the model improvements.