Traveling and steady waves in a supersonic jet and their interaction in linear and nonlinear approximations

This paper describes a study of curvature of gas trajectory at the initial section of a supersonic nonisobaric jet on the features of unsteady perturbations from the Kelvin–Helmholtz instability class. It is shown that, in the presence of a barrel-shaped structure, steady Taylor–Görtler perturbations in the form of longitudinal structures (banded formations) arise. Studies for a mixing layer with a Mach number $\mathrm{M}=1.5$ are carried out. The possibility of amplifying and suppressing the growth of Kelvin–Helmholtz perturbations by steady Taylor–Görtler waves. A nonlinear problem is solved within the framework of three-wave resonance interactions in a local-parallel approximation. A pumping wave is a steady Taylor–Görtler wave. It is shown that, at the initial section, small-amplitude traveling waves can be both amplified and suppressed.