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Thierry Faure

Publications and source records attributed to Thierry Faure.

2 recordsLinked to original sources
arXiv2007

Apparition de structures tourbillonnaires de type Görtler dans une cavité parallélépipédique ouverte de forme variable

The interaction between a laminar boundary layer and an open cavity is investigated experimentally for Reynolds numbers between 860 and 32300. Flow visualizations are carried out for different observation directions in order to understand the spatial development of dynamical structures. The study is conducted by changing the cavity length and height and the external flow velocity, and therefore the flow patterns inside the cavity. The issue is to emphasize the three-dimensional development of the flow. In particular, we show that the cavity dynamical structures are not due to secondary shear layer instabilities. Görtler-type vortices are developing inside the cavity for some parameters and their properties are discussed. The existence diagram of these instabilities is also provided.

physics.class-ph↗
arXiv2006

Développement d'instabilités dans un écoulement subsonique se développant au-dessus d'une cavité : mesures synchronisées PIV-LDV

A boundary layer interacting with a cavity is a benchmark case that is present in environmental applications, aeronautics, automobile aerodynamics or industrial applications, where the velocity over a rectangular cavity is relatively low. In the present investigation, the interaction between a laminar boundary layer with external velocity Ue and an open cavity is investigated experimentally for medium range Reynolds numbers (between 4600 and 18500) with flow diagnostics optical methods, for a cavity aspect ratio (length over depth) of two. A shear layer induces a main vortex and a counter-rotating secondary vortex inside the cavity. The shear layer also develops instabilities interacting with the downstream cavity edge. Particle image velocimetry (PIV) and laser Doppler velocimetry (LDV) measurements are synchronized in order to get global information of both spatial velocity fields and time-resolved signals in a particular position situated downstream of the development of the shear layer above the cavity. The PIV velocity fields are phase-averaged with a singular value decomposition of the LDV signal.

physics.class-ph↗