Study of the Turbulent Velocity Field in the Near Wake of a Bluff Body

Juan José Cruz Villanueva (1) , Luís Fernando Figueira da Silva (1, 2)

1 PUC-Rio - Pontifícia Universidade Católica do Rio de Janeiro [Brasil] = Pontifical Catholic University of Rio de Janeiro [Brazil] = Université catholique pontificale de Rio de Janeiro [Brésil]
2 PPrime [Poitiers] - Institut Pprime [UPR 3346]

An experimental characterization of the turbulent flow structure formed downstream of a vertically mounted circular bluff body is performed. Three components of an instantaneous velocity field are measured using the stereo particle image velocimetry technique at the symmetry plane. The average velocity and the turbulent properties are analyzed. The results indicate a recirculation zone consisting of a toroidal vortex with similar dimensions for all Reynolds numbers. The largest turbulent fluctuations are found at the stagnation point region. The observed anisotropy of the normal Reynolds stress components is associated with the stagnation point flow, whereas the crosscorrelation component extreme occurs in high strain rate regions. An analysis of the Reynolds tensor anisotropy using the Lumley triangle is performed, revealing that the largest departures from isotropy occur at high shear regions and also within the vortex.

Domaines: Milieux fluides et réactifs

Juan José Cruz Villanueva, Luís Fernando Figueira da Silva. Study of the Turbulent Velocity Field in the Near Wake of a Bluff Body. Flow, Turbulence and Combustion, 2016, 97 (3), pp.715-728. ⟨10.1007/s10494-016-9709-6⟩. ⟨hal-03313660⟩