Shock interactions in inviscid air and CO2-N2 flows in thermochemical non-equilibrium

The present study aims at providing insights into shockwave interference patterns in gas flows when amixture different than air is considered. High-energy non-equilibrium flows of air and CO2-N-2 over a double-wedge geometry are studied numerically. The impact of freestream temperature on the non-equilibrium shock interaction patterns is investigated by simulating two different sets of freestream conditions. To this purpose, the SU2 solver has been extended to account for the conservation of chemical species as well as multiple energies and coupled to the Mutation++ library (Multicomponent Thermodynamic And Transport properties for IONized gases in C++) that provides all the necessary thermochemical properties of the mixture and chemical species. An analysis of the shock interference patterns is presented with respect to the existing taxonomy of interactions. A comparison between calorically perfect ideal gas and non-equilibrium simulations confirms that nonequilibrium effects greatly influence the shock interaction patterns. When thermochemical relaxation is considered, a type VI interaction is obtained for the CO2-dominated flow, for both freestream temperatures of 300 K and 1000 K; for air, a type V six-shock interaction and a type VI interaction are obtained, respectively. We conclude that the increase in freestream temperature has a large impact on the shock interaction pattern of the air flow, whereas for the CO2-N-2 flow the pattern does not change.

Automated summary

The study provides insights into shockwave interference patterns in gas flows with different gas mixtures. It reveals that freestream temperature significantly influences the non-equilibrium shock interaction patterns.