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arXiv · 2311.10391

Interfacial instabilities in confined displacements involving non-Newtonian fluids

Vaibhav Raj Singh Parmar·Ranjini Bandyopadhyay
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Abstract

The growth of interfacial instabilities during fluid displacements can be driven by gradients in pressure, viscosity and surface tension, and by applying external fields. Since displacements of non-Newtonian fluids such as polymer solutions, colloidal and granular slurries are ubiquitous in natural and industrial processes, understanding the growth mechanisms and fully-developed morphologies of interfacial patterns involving non-Newtonian fluids is extremely important. In this perspective, we focus on {displacement experiments} wherein competition{s} between capillary, viscous, elastic and frictional forces drive the onset and growth of interfacial instabilities in confined geometries. We conclude by highlighting several exciting open problems in this research area.

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Vaibhav Raj Singh Parmar, Ranjini Bandyopadhyay. 2023-11-17. Interfacial instabilities in confined displacements involving non-Newtonian fluids. https://doi.org/10.1209/0295-5075%2Fad2d13

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