Numerical simulation of turbulent spots evolution in supersonic boundary layer over a plate

Direct numerical simulations of the turbulent spots evolution in the boundary layer on a flat plate at zero angle of attack at the freestream Mach number $\mathrm{M}_\infty=6$ has been carried out. Considered was the propagation of artificially excited localized three-dimensional vortical disturbances with different initial amplitudes, which, when propagating downstream, develop into turbulent spots. A direct numerical simulation was performed by solving the Navier-Stokes equations for three-dimensional compressible gas flows using the in-house solver that implements an implicit shock capturing numerical scheme. It is shown, that the universal quasi-monotone numerical scheme makes it possible to correctly estimate the main characteristics of turbulent spots — the transverse spreading angle and leading and trailing fronts velocities. The agreement between the obtained spots parameters and the results of other authors is demonstrated.