Experimental study of forced stratified turbulence

P. Augier (1) , P. Billant (1) , Maria-Eletta Negretti (1) , J.-M. Chomaz (1)

1 LadHyX - Laboratoire d'hydrodynamique

Recent results have shown that strongly stratified turbulence has a three dimensional dynamic instead of a quasi-two dimensional dynamic conjectured previously. The structures are strongly anisotropic with an aspect ratio scaling like the Froude number lv/lhFh [1]. A direct cascade of energy from large scales to small scales associated with a kh -5/3 horizontal kinetic energy spectrum has been predicted and observed in DNS of forced stratified turbulence when the buoyancy Reynolds number Rt is sufficiently large [2]. In constrast, for small Rt, the flow is dominated by vertical viscous effects even if the Reynolds number is large [3, 4].

Domains: Engineering Sciences [physics]; Mechanics [physics.med-ph]; Fluids mechanics [physics.class-ph]

P. Augier, P. Billant, Maria-Eletta Negretti, J.-M. Chomaz. Experimental study of forced stratified turbulence. 12th EUROMECH European Turbulence Conference, Sep 2009, Marburg, Germany. pp.397-400, ⟨10.1007/978-3-642-03085-7_95⟩. ⟨hal-01025993⟩