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arXiv · 1012.0882

Oscillatory Spreading and Surface Instability of a Non-Newtonian Fluid under Compression

Moutushi Dutta Choudhury·Subrata Chandra·Soma Nag·Shantanu Das·Sujata Tarafdar
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Abstract

Starch solutions, which are strongly non-Newtonian, show a surface instability, when subjected to a load. A droplet of the fluid is sandwiched between two glass plates and a weight varying from 1 to 5 kgs. is placed on the top plate. The area of contact between the fluid and plate increases in an oscillatory manner, unlike Newtonian fluids in a similar situation. The periphery moreover, develops a viscous fingering like instability, which is not expected under compression. We attempt to model the non-Newtonian nature of the fluid through a visco-elastic model incorporating generalized calculus. This is shown to exhibit a qualitatively similar oscillatory variation in the surface strain.

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Moutushi Dutta Choudhury, Subrata Chandra, Soma Nag, Shantanu Das, Sujata Tarafdar. 2010-12-04. Oscillatory Spreading and Surface Instability of a Non-Newtonian Fluid under Compression. https://arxiv.org/abs/1012.0882

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