I. O. Pogorelov

A universal approach to the verification of a numerical method for solving the Navier–Stokes equations is proposed, through which the dissipation properties of the method can be reliably assessed. The approach is based on viscous damping of weak elementary perturbations propagating in uniform flow. The corresponding theoretical solution allows one to determine the order of convergence of the numerical method.

A universal approach to the verification of a numerical method for solving the Navier–Stokes equations is proposed, through which the dissipation properties of the method can be reliably assessed. The approach is based on viscous damping of weak elementary perturbations propagating in uniform flow. The corresponding theoretical solution allows one to determine the order of convergence of the numerical method.

The two most likely sources of disturbances capable of triggering boundary layer turbulization over a smooth unswept wing of a supersonic airplane are considered in terms of the full Navier–Stokes equations: atmospheric turbulence and acoustic noise radiated by the turbulent boundary layer over the fuselage. The frequency wave characteristics of boundary layer disturbances over the wing are analyzed and the dominant mechanism of transition is revealed. The numerical results are compared with those of linear stability theory.

The influence of the entropy layer generated by a small bluntness of the flat plate leading edge on laminar-turbulent supersonic boundary layer transition in the wake behind isolated roughness elements located on the plate surface is studied when the bluntness radius is varied. The experiments are carried out at the Mach number M = 6 over the Reynolds number range (0.4–2.3) × 10⁶. The Reynolds number is calculated on the basis of the free-stream parameters at the point of roughness. The well-known correlation dependences are verified and the transition criterion is estimated.