Simulations of laminar boundary-layer flow encountering large-scale surface indentions

N. Beratlis, E. Balaras, Kyle Squires, A. Vizard

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

The transition from laminar to turbulent flow over dimples and grooves has been investigated through a series of direct numerical simulations. Emphasis has been given to the mechanism of transition and the momentum transport in the post-dimple boundary layer. It has been found that the dimple geometry plays an important role in the evolution of the turbulent boundary layer downstream. The mechanism of transition in all cases is that of the reorientation of the spanwise vorticity into streamwise oriented structures resembling hairpin vortices commonly encountered in wall bounded turbulent flows. Although qualitatively the transition mechanism amongst the three different cases is similar, important quantitative differences exist. It was shown that two-dimensional geometries like a groove are more stable than three-dimensional geometries like a dimple. In addition, it was found that the cavity geometry controls the initial thickness of the boundary layer and practically results in a shift of the virtual origin of the turbulent boundary layer. Important differences in the momentum transport downstream of the dimples exist but in all cases the boundary layer grows in a self-similar manner.

Original languageEnglish (US)
Article number035112
JournalPhysics of Fluids
Volume28
Issue number3
DOIs
StatePublished - Mar 1 2016

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laminar boundary layer
Laminar boundary layer
boundary layer flow
Boundary layer flow
Boundary layers
boundary layers
turbulent boundary layer
geometry
grooves
turbulent flow
Geometry
simulation
Turbulent flow
horseshoe vortices
momentum
Momentum
direct numerical simulation
vorticity
retraining
Direct numerical simulation

ASJC Scopus subject areas

  • Condensed Matter Physics

Cite this

Simulations of laminar boundary-layer flow encountering large-scale surface indentions. / Beratlis, N.; Balaras, E.; Squires, Kyle; Vizard, A.

In: Physics of Fluids, Vol. 28, No. 3, 035112, 01.03.2016.

Research output: Contribution to journalArticle

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