Non-Newtonian rheology in a capillary tube with varying radius

Federico Lanza; Alex Hansen; Alberto Rosso; Laurent Talon

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arXiv · 2106.04325

Non-Newtonian rheology in a capillary tube with varying radius

Federico Lanza·Alex Hansen·Alberto Rosso·Laurent Talon

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Abstract

The flow through a capillary tube with non-constant radius and where bubbles of yield stress fluid are injected is strongly non-linear. In particular below a finite yield pressure drop, $P_y$, flow is absent, while a singular behaviour is expected above it. In this paper we compute the yield pressure drop statistics and the mean flow rate in two cases: (i) when a single bubble is injected, (ii) when many bubbles are randomly injected in the fluid.

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Federico Lanza, Alex Hansen, Alberto Rosso, Laurent Talon. 2021-06-08. Non-Newtonian rheology in a capillary tube with varying radius. https://arxiv.org/abs/2106.04325

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