Vortex structure of the unstable jet studied on the basis of the Boltzmann equation

The properties of the transition to an unstable flow in the supersonic underexpanded free jet at small Knudsen numbers are studied. Possibilities of description of unstable turbulent flows on the basis of the Boltzmann kinetic equation are discussed. A system of streamwise vortices obtained in calculations is related to the Taylor–Goertler type of instability. This result is qualitatively conformed to experimental data.