On the influence of pressure variation on ignition and mixing processes in a reacting shock-bubble interaction

Abstract

We present numerical simulations of a reacting shock-bubble interaction with detailed chemistry. The interaction of the Richtmyer-Meshkov instability (RMI) and shock-induced ignition of a stoichiometric H2-O2 gas mixture are investigated. Different initial pressures in the range of po = 0.25-0.75 atm at a constant shock wave Mach number of Ma = 2.30 trigger different reaction wave types (deflagration and detonation). Low pressure reactions are dominated by H, O, OH production and high pressure chemistry is driven by HO2 and H2O2. The reaction wave type is crucial for the spatial and temporal evolution of the bubble. The RMI and subsequent Kelvin Helmholtz instabilities show a high reaction sensitivity. Mixing is significantly reduced by both types of reaction waves, with detonation waves showing the strongest effect.