Traveling and Steady Waves in a Supersonic Jet and their Interaction in Linear and Nonlinear Approximations
N. M. Terekhova
Khristianovich Institute of Theoretical and Applied Mechanics, Novosibirsk, 630090, Russia
Keywords: неизобарическая струя, слой смешения, неустойчивость Кельвина-Гельмгольца, неустойчивость Тейлора-Гертлера, nonisobaric jet, mixing layer, Kelvin-Helmholtz instability, Taylor-Gortler instability
Abstract
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-Gortler perturbations in the form of longitudinal structures (banded formations) arise. Studies for a mixing layer with a Mach number M=1.5 are carried out. The possibility of amplifying and suppressing the growth of Kelvin-Helmholtz perturbations by steady Taylor-Gortler 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-Gortler wave. It is shown that, at the initial section, small-amplitude traveling waves can be both amplified and suppressed.
|
