2009/04/17 by P. Delmont, P. DELMONT, R. Keppens +3
Engineering · Physics and Astronomy · #Computational Fluid Dynamics and Aerodynamics #Constant (computer programming) #Discontinuity (linguistics) #Fluid Dynamics and Heat Transfer #Instability #Laser-Plasma Interactions and Diagnostics #Oblique case #Perpendicular #Planar #Refraction #Shock (circulatory) #Vorticity #physics.flu-dyn #physics.plasm-ph
paper · pdf · doi:10.1017/s0022112009006028
21 pages, 17 figures in 41 ps-files, accepted by J. Fluid Mech
arxiv created 2009/04/17 · openalex publication_date 2009/05/12 · arxiv updated 2015/05/13 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We study the classical problem of planar shock refraction at an oblique density discontinuity, separating two gases at rest. When the shock impinges on the density discontinuity, it refracts, and in the hydrodynamical case three signals arise. Regular refraction means that these signals meet at a single point, called the triple point . After reflection from the top wall, the contact discontinuity becomes unstable due to local Kelvin–Helmholtz instability, causing the contact surface to roll up and develop the Richtmyer–Meshkov instability (RMI). We present an exact Riemann-solver-based solution strategy to describe the initial self-similar refraction phase, by which we can quantify the vorticity deposited on the contact interface. We investigate the effect of a perpendicular magnetic field and quantify how its addition increases the deposition of vorticity on the contact interface slightly under constant Atwood number. We predict wave-pattern transitions, in agreement with experiments, von Neumann shock refraction theory and numerical simulations performed with the grid-adaptive code AMRVAC. These simulations also describe the later phase of the RMI.