title: Reynolds number scaling of velocity increments in isotropic turbulence.
abstract: Using the largest database of isotropic turbulence available to date, generated by the direct numerical simulation (DNS) of the Navier-Stokes equations on an 8192^{3} periodic box, we show that the longitudinal and transverse velocity increments scale identically in the inertial range. By examining the DNS data at several Reynolds numbers, we infer that the contradictory results of the past on the inertial-range universality are artifacts of low Reynolds number and residual anisotropy. We further show that both longitudinal and transverse velocity increments scale on locally averaged dissipation rate, just as postulated by Kolmogorov's refined similarity hypothesis, and that, in isotropic turbulence, a single independent scaling adequately describes fluid turbulence in the inertial range.
authors.affiliation: Department of Physics and INFN, University of Rome Tor Vergata, Rome 00133, Italy and Department of Mechanical Engineering, New York University, New York 11201, USA.
authors.forename: Kartik P
authors.initials: KP
authors.lastname: Iyer
authors.affiliation: Departments of Physics and Mechanical Engineering and the Courant Institute of Mathematical Sciences, New York University, New York 11201, USA.
authors.forename: Katepalli R
authors.initials: KR
authors.lastname: Sreenivasan
authors.affiliation: Schools of Aerospace Engineering and Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, USA.
authors.forename: P K
authors.initials: PK
authors.lastname: Yeung