On linear and nonlinear stability of coaxial pipe flow

Linear and nonlinear stability of the flow between coaxial cylinders is investigated. The linear analysis is carried out within scope of temporal linear stability theory. The eigenvalue map is obtained with the collocation method based on Chebyshev polynomials. The nonlinear analysis is based on a novel parallel code for DNS of a coaxial pipe flow. It is shown that the major source of finite amplitude instability is associated with the interaction of three-dimensional disturbances and stream wise rolls