Overview

Gkyell application illustration

Gkeyll ten-moment multifluid code solves the continuity, momentum, and pressure tensor equations of both protons and electrons, as well as the full Maxwell equations. Non-ideal effects like the Hall effect, inertia, and tensorial pressures are self-consistently embedded without the need to explicitly solve a generalized Ohm's law. Previously, we have benchmarked this approach in classical test problems like the Orszag-Tang vortex and GEM reconnection challenge problem. For heliophysics and planetary science problems, we have simulated the global magnetospheres of Ganymede [1], Mercury [2], Earth [3], and Uranus [4] in addition to local physics problems [5-12], such as anti-parallel reconnection, asymmetric reconnection, island coalescence, and drift instabilities.

Gkeyll framework (including the multi-moment multifluid code) is publicly available at https://github.com/ammarhakim/gkyl

References:

[1] L. Wang, K. Germaschewski, A. Hakim, C. Dong, J. Raeder, A. Bhattacharjee (2019). Electron Physics in 3D Two-Fluid Ten-Moment Modeling of Ganymede's Magnetosphere. Journal of Geophysical Research: Space Physics, 123, 2815–2830.    https://doi.org/10.1002/2017JA024761

[2] C. Dong, L. Wang, A. Hakim, A. Bhattacharjee, J. A. Slavin, G. A. DiBraccio, K. Germaschewski (2019). Global Ten-Moment Multifluid Simulations of the Solar Wind Interaction with Mercury: From the Planetary Conducting Core to the Dynamic Magnetosphere. Geophysical Research Letters, 46, 11584–11596.    https://doi.org/10.1029/2019GL083180

[3] L. Wang, A. Hakim, J. Ng, C. Dong, K. Germaschewski (2020). Exact and Locally Implicit Source Term Solvers for Multifluid-Maxwell Systems. Journal of Computational Physics, 415, 109510.    https://doi.org/10.1016/j.jcp.2020.109510

[4] S. Jarmak, E. Leonard, A. Akins, E. Dahl, D. R. Cremons, S. Cofield, A. Curtis, C. Dong, E. T. Dunham, B. Journaux, D. Murakami, W. Ng, M. Piquette, A. P. Girija, K. Rink, L. Schurmeier, N. Stein, N. Tallarida, M. Telus, L. Lowes, C. Budney, K. L. Mitchell (2020). QUEST: A New Frontiers Uranus Orbiter Mission Concept Study. Acta Astronautica, 170, 6–26.    https://doi.org/10.1016/j.actaastro.2020.01.030

[5] L. Wang, A. Hakim, A. Bhattacharjee, K. Germaschewski (2015). Comparison of multi-fluid moment models with particle-in-cell simulations of collisionless magnetic reconnection. Physics of Plasmas, 22 12108.    https://doi.org/10.1063/1.4906063

[6] J. Ng, Y.-M. Huang, A. Hakim, A. Bhattacharjee, A. Stanier, W. Daughton, L. Wang, and K. Germaschewski (2015). The island coalescence problem: Scaling of reconnection in extended fluid models including higher-order moments. Physics of Plasmas, 22(11), 112104.    https://doi.org/10.1063/1.4935302

[7] J. Ng, A. Hakim, A. Bhattacharjee, A. Stanier, and W. Daughton (2017). Simulations of anti-parallel reconnection using a nonlocal heat flux closure. Physics of Plasmas, 24, 82112.    https://doi.org/10.1063/1.4993195

[8] J. Ng, A. Hakim, and A. Bhattacharjee (2018). Using the maximum entropy distribution to describe electrons in reconnecting current sheets. Physics of Plasmas, 25, 82113.    https://doi.org/10.1063/1.5041758

[9] J. Ng, A. Hakim, J. Juno, and A. Bhattacharjee (2019). Drift instabilities in thin current sheets using a two-fluid model with pressure tensor effects. Journal of Geophysical Research: Space Physics, 124, 3331–3346.    https://doi.org/10.1029/2018JA026313

[10] J. TenBarge, J. Ng, J. Juno, L. Wang, A. Hakim, A. Bhattacharjee (2019). An extended MHD study of the 16 October 2015 MMS diffusion region crossing. Journal of Geophysical Research: Space Physics, 124, 8474–8487.    https://doi.org/10.1029/2019JA026731

[11] J. Ng, A. Hakim, L. Wang, A. Bhattacharjee (2020). An improved ten-moment closure for reconnection and instabilities. Physics of Plasmas 27, 082106.    https://doi.org/10.1063/5.0012067

[12] J. Ng, L.-J. Chen, A. Hakim, A. Bhattacharjee (2020). Reconstruction of electron and ion distribution functions in a magnetotail reconnection diffusion region. Journal of Geophysical Research: Space Physics 125, e2020JA027879.    https://doi.org/10.1029/2020JA027879