Propagation mechanism of localized wave packet in plane-Poiseuille flow
arXiv:2009.05213 · doi:10.1063/5.0042346
Abstract
The convection velocity of localized wave packet in plane-Poiseuille flow is found to be determined by a solitary wave at the centerline of a downstream vortex dipole in its mean field after deducting the basic flow. The fluctuation component following the vortex dipole oscillates with a global frequency selected by the upstream marginal absolute instability, and propagates obeying the local dispersion relation of the mean flow. By applying localized initial disturbances, a nonzero wave-packet density is achieved at the threshold state, suggesting a first order transition.
arXiv comment5 pages, 4 figures
References in corpus (11)
- A Universal Transition to Turbulence in Channel Flow
- Ecological collapse and the emergence of traveling waves at the onset of shear turbulence
- Universal continuous transition to turbulence in a planar shear flow
- Bifurcations to turbulence in transitional channel flow
- Directed percolation describes lifetime and growth of turbulent puffs and slugs
- Extended localized structures and the onset of turbulence in channel flow
- The growth mechanism of turbulent bands in channel flow at low Reynolds numbers
- Streamwise localization of traveling wave solutions in channel flow
- Streamwise decay of localized states in channel flow
- The Unified Transition Stages in Linearly Stable Shear Flows
- Chaotic self-sustaining structure embeded in turbulent-laminar interface