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Abstract. It is generally accepted that modeling Farley–Buneman instabilities requires resolving ion Landau damping to reproduce experimentally observed features. Particle-in-cell (PIC) simulations have been able to reproduce most of these but at a computational cost that severely affects their scalability. This limitation hinders the study of non-local phenomena that require three dimensions or coupling with larger-scale processes. We argue that a form of the five-moment fluid system can recreate several qualitative aspects of Farley–Buneman dynamics such as density and phase speed saturation, wave turning, and heating. Unexpectedly, these features are still reproduced even without using artificial viscosity to capture Landau damping. Comparing the proposed fluid models and a PIC implementation shows good qualitative agreement.
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Hybrid plasma simulations of Farley-Buneman instabilities in the auroral E-region
We implemented a hybrid continuous solver for fluid electrons and kinetic ions. Because the simulation is continuous, numerical noise is not an issue as it is for particle-in-cell approaches. Moreover, given that the ion kinetic equation is solved using a characteristic based method, no particle pushes have to be done. Our main goals are to reduce the computational cost of the simulations proposed by Kovalev (Kovalev et al., 2008, https://doi.org/10.5194/angeo2628532008) and reproduce the main experimental features of Farley-Buneman instabilities measured by radars and rockets. The equations were derived from first principles using the approximations that are satisfied in the auroral E-region. Various tests will be presented to assess numerical accuracy. With the proposed numerical framework, we are able to recover important nonlinear features associated with Farley-Buneman instabilities: wave turning of dominant modes, and saturation of density irregularities at values consistent with experiments.
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- Award ID(s):
- 1818216
- PAR ID:
- 10233658
- Date Published:
- Journal Name:
- Journal of geophysical research
- ISSN:
- 2169-9402
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/https://doi.org/10.1029/2020JA028379
