Next-generation OpenGGCM: Progress on Using Multi-fluid Moment Models for Geospace Simulations

With Earth's geospace plasma environment being nearly collisionless, it is necessary to go beyond one-fluid MHD to appropriately model the microphysics supporting small-scale dynamics and, in particular, magnetic reconnection. Multi-fluid moment models have previously shown promise to incorporate ion and electron scale kinetic physics, like off-diagonal pressure tensor elements supporting the reconnection electric field, in simplified model systems and in global simulations of Jupiter's moon Ganymede.

We will present the status of the newly developed next-generation OpenGGCM that has been developed to support multiple plasma models, from single-fluid MHD through Hall-MHD to multi-fluid moment models. We will describe the numerical challenges that come with the need to resolve a large range of scales reaching from the global magnetosphere scales to kinetic ion and electron scales, which requires adaptivity in the spatial domain to be computationally feasible, and show first applications of the new model to simulate reconnection at Earth's magnetosphere.