Localized structures on the edge in boundary layers and their traces in bypass transition

Abstract eng:
Investigation of the laminar–turbulent separatrix is performed in a boundary-layer flow. Constant homogeneous suction is applied at the wall in order to prevent the spatial growth of the layer, leading to the parallel Asymptotic Suction Boundary Layer (ASBL). Edge tracking is performed in a large computational domain allowing for full spatial localization on the separatrix. The obtained localized structure experiences recurrent dynamics going through calm and bursting phases. During calm phases the structure’s active core consists of a single low-speed streak which develops sinuous instabilities leading to a burst in energy. During the burst new streaks are created, with the structure growing in size and its core drifting in both planar directions. The recurrent simple structure observed during calm phases is compared with those seen in the early development of the minimal seed and during bypass transition. The implications on the dynamical systems view of the transition process are discussed.

• Export as: BibTeX | MARC | MARCXML | DC | EndNote | NLM | RefWorks
• Add to your basket