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arXiv · 1809.09648

Effect of polymer-stress diffusion in the numerical simulation of elastic turbulence

Anupam Gupta·Dario Vincenzi
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Abstract

Elastic turbulence is a chaotic regime that emerges in polymer solutions at low Reynolds numbers. A common way to ensure stability in numerical simulations of polymer solutions is to add artificially large polymer-stress diffusion. In order to assess the accuracy of this approach in the elastic-turbulence regime, we compare numerical simulations of the two-dimensional Oldroyd-B and FENE-P models sustained by a cellular force with and without artificial diffusion. We find that artificial diffusion can have a dramatic effect even on the large-scale properties of the flow and we show some of the spurious phenomena that may arise when artificial diffusion is used.

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Anupam Gupta, Dario Vincenzi. 2019-03-07. Effect of polymer-stress diffusion in the numerical simulation of elastic turbulence. https://doi.org/10.1017/jfm.2019.224

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