The structures responsible for the inverse energy and the forward enstrophy cascades in two-dimensional turbulenceC.-H. Bruneau1, P. Fischer1 and H. Kellay2
1 MAB, Université Bordeaux 1, CNRS UMR 5466, INRIA projet MC2 - 351 cours de la Libération, 33405 Talence, France
2 CPMOH, Université Bordeaux 1, CNRS UMR 5798 - 351 cours de la Libération, 33405 Talence, France
received 25 January 2007; accepted in final form 27 March 2007; published May 2007
published online 27 April 2007
Two-dimensional turbulence admits two different ranges: an inverse energy cascade at large scales and a cascade of enstrophy to the small scales. Here we show that two flow structures govern the transfers of either enstrophy or energy. Vortical structures are responsible for the transfers of energy upscale while filamentary structures are responsible for the forward transfer of the enstrophy.
47.27.Ak - Fundamentals.
47.27.Gs - Isotropic turbulence; homogeneous turbulence.
© Europhysics Letters Association 2007