ENERGY-SPECTRUM IN THE DISSIPATION RANGE OF FLUID TURBULENCE

High-resolution, direct numerical simulations of three-dimensional inc ompressible Navier-Stokes equations are carried out to study the energ y spectrum in the dissipation range. An energy spectrum of the form A (k/k(d))(alpha)exp[-beta k/k(d)] is confirmed. The possible values of the parameters alpha and beta, as well as their dependence on Reynolds numbers and length scales, are investigated, showing good agreement w ith recent theoretical predictions. A 'bottleneck'-type effect. is rep orted at k/k(d) approximate to 4, exhibiting a possible transition fro m near-dissipation to far-dissipation.