Fluid dynamics and jamming in a dilatant fluid

Hiizu Nakanishi; Namiko Mitarai

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arXiv · 1010.5063

Fluid dynamics and jamming in a dilatant fluid

Hiizu Nakanishi·Namiko Mitarai

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Abstract

We present a phenomenological fluid dynamics model for a dilatant fluid, i.e. a severe shear thickening fluid, by introducing a state variable. The Navier-Stokes equation is coupled with the state variable field, which evolves in response to the local shear stress as the fluid is sheared. The viscosity is assumed to depend upon the state variable and to diverge at a certain value due to jamming. We demonstrate that the coupling of the fluid dynamics with the shear thickening leads to an oscillatory instability in the shear flow. The model also shows a peculiar response of the fluid to a strong external impact.

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Hiizu Nakanishi, Namiko Mitarai. 2010-10-25. Fluid dynamics and jamming in a dilatant fluid. https://arxiv.org/abs/1010.5063

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