Mixing by polymers: experimental test of decay regime of mixing

T. Burghelea; E. Segre; V. Steinberg

doi:10.1103/physrevlett.92.164501

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Mixing by polymers: experimental test of decay regime of mixing

T. Burghelea·E. Segre·V. Steinberg

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Abstract

By using high molecular weight fluorescent passive tracers with different diffusion coefficients and by changing the fluid velocity we study dependence of a characteristic mixing length on the Peclet number, $Pe$, which controls the mixing efficiency. The mixing length is found to be related to $Pe$ by a power law, $L_{mix}\propto Pe^{0.26\pm 0.01}$, and increases faster than expected for an unbounded chaotic flow. Role of the boundaries in the mixing length abnormal growth is clarified. The experimental findings are in a good quantitative agreement with the recent theoretical predictions.

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T. Burghelea, E. Segre, V. Steinberg. 2004-03-07. Mixing by polymers: experimental test of decay regime of mixing. https://doi.org/10.1103/physrevlett.92.164501

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