The Richtmyer–Meshkov instability (RMI) results from the impulsive acceleration of a density interface where the RMI itself or the acceleration is perturbed. The RMI is ubiquitous in shock environments and may arise due to an interface of fluid species, isotopes, temperature, or more. The plasma RMI can be significantly influenced by electromagnetic effects and can be modeled more accurately by a multi-fluid plasma (MFP) model rather than conventional magnetohydrodynamics, though with increased computational expense. MFP modeling of the plasma RMI has revealed many phenomena but has only been completed within the ideal regime. Modeling the effects of elastic collisions is vital for understanding the behavior of the instability in a dense plasma. The Braginskii transport coefficients provide theoretically based relations modeling thermal equilibration, inter-species drag, viscous momentum- and energy-transfers, and thermal conductivity. Our numerical simulations of the MFP RMI with these relations show that the key changes from the ideal case are (1) reduction of relative motion between the ion and electron fluids (consequently affecting the self-generated electromagnetic fields), (2) introduction of anisotropy in momentum and energy via transport coefficients, and (3) damping of high frequency electromagnetic waves and plasma waves. Under the conditions studied, the net effect is a reduction in the MFP RMI amplitude width and the growth rate to levels approaching the neutral fluid instability, as well as a reduction in large scale perturbations along the ion fluid density interface, a positive for inertial confinement fusion efforts. There are, however, two important caveats: small-scale density interface perturbations remain, and the conditions simulated are a few relevant points in a large parameter space that requires further investigation.
|Original language||English (US)|
|Journal||Physics of Plasmas|
|State||Published - Feb 17 2023|
Bibliographical noteKAUST Repository Item: Exported on 2023-02-20
Acknowledged KAUST grant number(s): URF/1/2162-01
Acknowledgements: This research was supported by the KAUST Office of Sponsored Research under Award No. URF/1/2162-01, and computational resources were provided by the Australian Government under the National Computational Merit Allocation Scheme. We dedicate this work to the memory of Professor Ravi Samtaney who passed away in 2022. Ravi was a passionate and exceptional academic who dedicated himself to computational and theoretical research in several disciplines, including computational fluid dynamics and plasma physics. Ravi's humour, generosity, and scientific curiosity made him an exceptional researcher, colleague, and mentor.
This publication acknowledges KAUST support, but has no KAUST affiliated authors.
ASJC Scopus subject areas
- Condensed Matter Physics