HYDRODYNAMIC STABILITY OF SWIRLING FLOWS WITH AXIAL RECIRCULATION ZONES

The problem of the motion of a viscous incompressible swirling flow in an axisymmetric channel has been numerically investigated. Various flow regimes have been obtained, including those with the formation of the axial recirculation zones. In the framework of linear theory, the stability of the obtained calculated flows with respect to non-axisymmetric perturbations is investigated on the assumption of local parallelism. The growth rates and phase velocities of unstable disturbances are calculated. In the presence of a reverse flow zone, the disturbances growth rates are increased significantly.