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arXiv · 1003.5331

Strong polymer-turbulence interactions in viscoelastic turbulent channel flow

Vassilios Dallas·J. Christos Vassilicos·Geoffrey F. Hewitt
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Abstract

This paper is focused on the fundamental mechanism(s) of viscoelastic turbulence that lead to polymer induced turbulent drag reduction phenomenon. A great challenge in this problem is the computation of viscoelastic turbulent flows, since the understanding of polymer physics is restricted to mechanical models. An effective state-of-the-art numerical method to solve the governing equation for polymers modelled as non-linear springs, without using any artificial assumptions as usual, was implemented here for the first time on a three-dimensional channel flow geometry. The capability of this algorithm to capture the strong polymer-turbulence dynamical interactions is depicted on the results, which are much closer qualitatively to experimental observations. This allowed a more detailed study of the polymer-turbulence interactions, which yields an enhanced picture on a mechanism resulting from the polymer-turbulence energy transfers.

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Vassilios Dallas, J. Christos Vassilicos, Geoffrey F. Hewitt. 2010-03-27. Strong polymer-turbulence interactions in viscoelastic turbulent channel flow. https://doi.org/10.1103/physreve.82.066303

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