ИСТИНА

The phenomenon of the high-speed buffet onset is investigated when a transonic flow is flown around the NACA0012 airfoil. A mathematical model based on high-order approximation algorithms is proposed, which allows calculating unsteady separated flows. The model is formed on the integration of quasi-hydrodynamic equations. A parametric study of the high-speed viscous gas flow around the airfoil is carried out, depending on the angle of attack. Both instantaneous and averaged flow patterns are analyzed. Pulsation of flow characteristics distributions at different attack angles are obtained. The regularities of the boundary layer separation occurrence are revealed. The shock waves influence on the flow regime near the airfoil surface is determined. The critical attack angle of high-speed buffet onset is determined.