FROM SMALL SCALES TO LARGE SCALES IN 3-DIMENSIONAL TURBULENCE - THE EFFECT OF DILUTED POLYMERS

In a turbulent flow, diluted polymers are shown to inhibit the formation of coherent high-vorticity filaments and to reduce correspondingly the rate of formation of large eddies. This effect demonstrates that in a three-dimensional turbulent flow, some nondissipative small-scale structures, the vorticity filaments, are nuclei of formation of large-scale structures. The reduction of the energy dissipation rate also suggests that this breakdown of the vorticity filaments into eddies is important for the formation of the dissipative structures.