Gas Injection and Suction Effect on the Instability of a Supersonic Boundary Layer

• Published in: Fluid dynamics 2023-04, Vol.58 (2), p.232-239
• Main Authors: Novikov, A. V., Obraz, A. O., Timokhin, D. A.
• Format: Article
• Language: English
• Subjects: Boundary layer stability; Classical and Continuum Physics; Classical Mechanics; Compressible flow; Destabilization; Disturbances; Engineering Fluid Dynamics; Flat plates; Fluid- and Aerodynamics; Gas injection; Laminar flow; Mach number; Numerical models; Physics; Physics and Astronomy; Stability analysis; Suction; Supersonic boundary layers
• ISSN: 0015-4628; 1573-8507
• DOI: 10.1134/S001546282260184X

We present the results of an investigation of the boundary layer stability on a flat plate having a region of gas injection/suction normal to the wall at a large supersonic freestream Mach number. The laminar flow past a flat plate having a region of distributed injection/suction of fixed intensity is modeled numerically using the integration of Navier—Stokes equations. The unstable disturbances in the boundary layer distorted by injection/suction are analyzed within the framework of the linear stability theory and the method for compressible flows. High-frequency disturbances belonging to the plane second mode of the boundary layer, which are the most unstable at high velocities, are considered. It is shown that gas injection/suction leads to a nonmonotonic variation of disturbance growth rates with the appearance of stabilization/destabilization regions, as compared with the case in which injection/suction is absent.