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arXiv · math/0703097

The inertial dynamics of thin film flow of non-Newtonian fluids

Abstract

Consider the flow of a thin layer of non-Newtonian fluid over a solid surface. I model the case of a viscosity that depends nonlinearly on the shear-rate; power law fluids are an important example, but the analysis here is for general nonlinear dependence. The modelling allows for large changes in film thickness provided the changes occur over a large enough lateral length scale. Modifying the surface boundary condition for tangential stress forms an accessible base for the analysis where flow with constant shear is a neutral critical mode, in addition to a mode representing conservation of fluid. Perturbatively removing the modification then constructs a model for the coupled dynamics of the fluid depth and the lateral momentum. For example, the results model the dynamics of gravity currents of non-Newtonian fluids even when the flow is not very slow.

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BibTeXRIS

A. J. Roberts. 2007-03-03. The inertial dynamics of thin film flow of non-Newtonian fluids. https://doi.org/10.1016/j.physleta.2007.10.014

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