Pumping viscoelastic two-fluid media

Hirofumi Wada

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arXiv · 1004.1254

Pumping viscoelastic two-fluid media

Hirofumi Wada

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Abstract

Using a two-fluid model for viscoelastic polymer solutions, we study analytically fluid transport driven by a transverse, small amplitude traveling wave propagation. The pumping flow far from the waving boundary is shown to be strongly wave number and viscosity dependent, in contrast to a viscous Newtonian fluid. We find the two qualitatively different regimes: In one regime relevant to small wave numbers, the fluidic transport is almost the same as the Newtonian case, and uniform viscoelastic constitutive equations provide a good approximation. In the other regime, the pumping is substantially decreased because of the gel-like character. The boundary separating these two regimes is clarified. Our results suggest possible needs of two-fluid descriptions for the transport and locomotion in biological fluids with cilia and flagella.

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Hirofumi Wada. 2010-04-08. Pumping viscoelastic two-fluid media. https://arxiv.org/abs/1004.1254

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