GALCIT Colloquium

The Richtmyer–Meshkov instability (RMI) occurs when a perturbed density interface is impulsively accelerated. This is common in shock laden environments such as supernovae, fusion experiments, and hypersonic air-breathing engines and test facilities. Density interfaces may arise due to discontinuities in fluid species, phase, temperature, and more. In many important applications, the fluids involved in the instability are plasmas, which can be significantly influenced by electromagnetic effects. Modelling the plasma RMI with the ideal multi-fluid plasma (MFP) model revealed electric field driven secondary instabilities that drive more severe interfacial instability than predicted by conventional magnetohydrodynamics. This seminar will focus on extending MFP modeling of the RMI to include the effects of elastic collisions, vital for understanding its behavior in a dense plasma. The Braginskii transport coefficients are utilized to model thermal equilibration, inter-species drag, viscous momentum and energy transfers, and thermal conductivity. Numerical simulations of the collisional MFP RMI at conditions relevant to inertial confinement fusion show major changes from the ideal case. The most significant is due interspecies collisions reducing of relative motion between the ion and electron fluids, which is responsible for self-generated electromagnetic fields and the secondary instabilities they drive. The influence of an applied magnetic field on the collisional plasma RMI will also be explored.