The evolution of the three-dimensional time-developing mixing layer is simulated numerically using the pseudo-spectral method. The initial perturbations used in this study consisted of the two-dimensional fundamental wave and the streamwise-invariant three-dimensional disturbance. A comparison of the formations of the streamwise vortices with different amplitude functions for three-dimensional disturbances is made. In one case the results are similar to that of Rogers & Moser, whereas a different way in which the quadrupole forms and sudden expansion of the rib are observed in another case. The simulation also confirms that the stretching by the forming roller rather than Rayleigh centrifugal instability is responsible for the formation of the rib. Finally, numerical flow visualization results are presented.
Rogers MM, Moser RD. The three-dimensional evolution of a plane mixing layer: the Kelvin-Helmholtz rollup.J Fluid Mech, 1992, 243: 183–226MATHCrossRefGoogle Scholar
Moser RD, Rogers MM. The three-dimensional evolution of a plane mixing layer: pairing and transition to turbulence.J Fluid Mech, 1993, 247: 275–320MATHCrossRefGoogle Scholar
Lasheras JC, Choi H. Three-dimensional instability of a plane free shear layer: an experimental study of the formation and evolution of streamwise vortices.J Fluid Mech, 1988, 189: 53–86CrossRefGoogle Scholar
Leboeuf RL, Mehta RD. Vortical structure morphology in the region of a forced mixing layer: roll-up and pairing.J Fluid Mech, 1996, 315: 175–221CrossRefGoogle Scholar
Nygaard KJ, Glezer A. Core instability of the spanwise vortices and generation of small-scale motion in a plane mixing layer.J Fluid Mech, 1990, 231: 257–301CrossRefGoogle Scholar
Lin SJ, Corcos GM. The mixing layer: deterministic models of a turbulent flow. Part 3. The effect of plane strain on the dynamics of streamwise vortices.J Fluid Mech, 1984, 141: 139–178MATHCrossRefGoogle Scholar
Zhang Hongquan. Streamwise vortices in a plane mixing layer and Rayleigh's centrifugal instability.Acta Mechanica Sinica, 1997, 29: 129–135 (in Chinese)Google Scholar