Universality of anisotropic fluctuations from numerical simulations of turbulent flows
Abstract
We present new results from a direct numerical simulation of a threedimensional homogeneous RayleighBénard system (HRB), i.e. a convective cell with an imposed linear mean temperature profile along the vertical direction. We measure the SO(3)decomposition of both velocity structure functions and buoyancy terms. We give a dimensional prediction for the values of the anisotropic scaling exponents in this RayleighBénard systems. Measured scaling does not follow dimensional estimate, while a better agreement can be found with the anisotropic scaling of a different system, the randomKolmogorovflow (RKF) (Biferale L., Daumont I., Lanotte A. and Toschi F. Phys. Rev. E, 66 (2002) 056306). Our findings support the conclusion that scaling properties of anisotropic fluctuations are universal, i.e. independent of the forcing mechanism sustaining the turbulent flow.
 Publication:

EPL (Europhysics Letters)
 Pub Date:
 November 2003
 DOI:
 10.1209/epl/i2003002339
 arXiv:
 arXiv:nlin/0302036
 Bibcode:
 2003EL.....64..461B
 Keywords:

 47.27.Ak;
 47.27.Eq;
 47.27.Te;
 Fundamentals;
 Nonlinear Sciences  Chaotic Dynamics
 EPrint:
 4 pages, 3 figures