The question whether the vortex dynamics and structure at small scales have significant influence on the statistics at large scales is addressed on the basis of quantitative comparison of two turbulent fields. One is a reference field generated by direct numerical simulation of turbulence of an incompressible fluid obeying the Navier-Stokes (NS) equation in a periodic box. The other is an artificial field in which the coherent vortical structures at small scales (similar to eta) that could be formed by the NS dynamics in the reference field are destroyed by an artificial computational operation, where eta is the Kolmogorov micro-length scale. The comparison of the two fields suggests that the statistics at larger scale (eta) are not sensitive to the exact vortex dynamics and structure, at least in the case studied here. (C) 2015 AIP Publishing LLC.
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