The Richtmyer–Meshkov instability of thermal, isotope and species interfaces in a five-moment multi-fluid plasma

K.C. Tapinou, V. Wheatley, D. Bond, Ingo Jahn

Research output: Contribution to journalArticlepeer-review

4 Scopus citations


The Richtmyer–Meshkov instability (RMI) results from the impulsive acceleration of a density interface where either it or the acceleration is perturbed. Density interfaces may arise due to a change in gas species, isotope, temperature or a combination of these. We computationally investigate the effect of interface type on the plasma RMI, which is relevant for a range of applications, including inertial confinement fusion. We simulate the evolution of single-mode perturbed thermal, species and isotope interfaces in an ideal ion–electron plasma using the multi-fluid plasma (MFP) model. We find that, in the MFP model, the evolution of different types of interface differs significantly, in contrast to single-fluid models where they behave similarly if the Atwood number is matched. The thermal and species interfaces produce the most severe response to shock acceleration, experiencing the secondary instabilities and enhanced primary mode growth. The isotope interface evolution is restrained in comparison with the former cases, resembling the response predicted by single-fluid models. The determining factor in the severity of the MFP RMI is the density ratio across the initial interface in the electron fluid, which is unity for an isotope interface. We observe that, as the density ratio across the electron interface decreases, so do the magnitudes of the self-generated fields and consequently the severity of the growth amplification. Generally, the evolution of the RMI with different types of interface becomes more similar as the level of coupling between the ion and electron fluids is increased, characterised by reducing the plasma non-dimensional skin depth.
Original languageEnglish (US)
JournalJournal of Fluid Mechanics
StatePublished - Nov 3 2022
Externally publishedYes

Bibliographical note

KAUST Repository Item: Exported on 2022-11-08
Acknowledged KAUST grant number(s): URF/1/2162-01
Acknowledgements: This research was supported by the KAUST Office of Sponsored Research under Award URF/1/2162-01. This work was supported by computational resources provided by the Australian Government under the National Computational Merit Allocation Scheme. Special thanks to L. Whyborn for providing feedback on an early draft of this paper.
This publication acknowledges KAUST support, but has no KAUST affiliated authors.

ASJC Scopus subject areas

  • Mechanics of Materials
  • Mechanical Engineering
  • Condensed Matter Physics


Dive into the research topics of 'The Richtmyer–Meshkov instability of thermal, isotope and species interfaces in a five-moment multi-fluid plasma'. Together they form a unique fingerprint.

Cite this