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Manifestations of Drag Reduction by Polymer Additives in Decaying, Homogeneous, Isotropic Turbulence

Prasad Perlekar·Dhrubaditya Mitra·Rahul Pandit
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Abstract

The existence of drag reduction by polymer additives, well established for wall-bounded turbulent flows, is controversial in homogeneous, isotropic turbulence. To settle this controversy we carry out a high-resolution direct numerical simulation (DNS) of decaying, homogeneous, isotropic turbulence with polymer additives. Our study reveals clear manifestations of drag-reduction-type phenomena: On the addition of polymers to the turbulent fluid we obtain a reduction in the energy dissipation rate, a significant modification of the fluid energy spectrum especially in the deep-dissipation range, a suppression of small-scale intermittency, and a decrease in small-scale vorticity filaments.

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Prasad Perlekar, Dhrubaditya Mitra, Rahul Pandit. 2006-09-27. Manifestations of Drag Reduction by Polymer Additives in Decaying, Homogeneous, Isotropic Turbulence. https://doi.org/10.1103/physrevlett.97.264501

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