A brief review is given of numerical simulation results for the evolution of disturbances in a flat oscillatory Stokes layer. A spatially localised form of impulsive forcing is applied to trigger the disturbances. For the linearized case, the disturbance development displays an intriguing family tree-like structure, which involves the birth of successive generations of wavepackets. Although some features of the wavepacket behaviour may be accounted for using a Floquet linear stability analysis, for Fourier modes with prescribed wavenumbers, the discovery of the tree-like structure was completely unexpected. Simulation results were also obtained for nonlinear disturbances, where highly localised spikes were found to develop.
|Number of pages||4|
|Publication status||Published - 2015|
|Event||8th IUTAM-ABCM Symposium on Laminar Turbulent Transition, LTT 2014 - Rio de Janeiro, Brazil|
Duration: 8 Sep 2014 → 12 Sep 2014
Bibliographical noteCopyright the Author(s) 2015. Version archived for private and non-commercial use with the permission of the author/s and according to publisher conditions. For further rights please contact the publisher.
- boundary layer
- Floquet stability
- impulse response
- Unsteady flow
- wavepacket evolution