Computational and theoretical study of a shock wave interacting with a zone of turbulent mixing occurring on an air – argon flat boundary in experiments with a shock tube

This paper describes the formulation and calculation results pertaining to the Euler gas aerodynamic complex (EGAC) method of interaction between a shock wave and a turbulent mixing zone, which develops on a flat contact boundary separating air and argon. The study is carried out using both direct numerical three-dimensional modeling and a two-dimensional $(k-\varepsilon)$ turbulence model. A comparison is made with the results of experiments in which the expansion and stratification of a shock wave is observed during its propagation after passing through a turbulent mixing zone. Calculations are carried out using the $(k-\varepsilon)$ model and with account for the presence of a boundary layer, which make it possible to explain this effect.