Non-Newtonian rheology in a capillary tube with varying radius

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, PyPy, 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.

Federico Lanza 1, 2 Alex Hansen 2 Alberto Rosso 1 Laurent Talon 3
1 LPTMS – Laboratoire de Physique Théorique et Modèles Statistiques
2 NTNU – Norwegian University of Science and Technology [Trondheim]
3 FAST – Fluides, automatique, systèmes thermiques