Wall Friction and Effective Viscosity of a Homogeneous Dispersed Liquid-Liquid Flow in a Horizontal Pipe

Amélie Pouplin (1, 2) , Olivier Masbernat (1) , Sandrine Decarre (2) , Alain Liné (3)

1 LGC - Laboratoire de Génie Chimique
2 IFPEN - IFP Energies nouvelles
3 LISBP - Laboratoire d'Ingénierie des Systèmes Biologiques et des Procédés

Homogenous oil in water dispersion has been investigated in a horizontal pipe. The mean droplet size is 25 μm. Experiments were carried out in a 7.5-m-long transparent pipe of 50-mm internal diameter. The wall friction has been measured and modeled for a wide range of flow parameters, mixture velocities ranging from 0.28 to 1.2 m/s, and dispersed phase volume fractions up to 0.6, including turbulent, intermediate, and laminar regimes. Flow regimes have been identified from velocity profiles measured by particle image velocimetry in a matched refractive index medium. It is shown that the concept of effective viscosity is relevant to scale the friction at the wall of the dispersed flow. Based on mixture properties, the friction factor follows the Hagen-Poiseuille and the Blasius' law in laminar and turbulent regimes, respectively. Interestingly, the transition toward turbulence is delayed as the dispersed phase fraction is increased.

Mots clés: liquid-liquid pipe flow; homogeneous dispersed flow; PIV; effective viscosity; wall friction

Domaines: Mécanique des fluides [physics.class-ph]

Amélie Pouplin, Olivier Masbernat, Sandrine Decarre, Alain Liné. Wall Friction and Effective Viscosity of a Homogeneous Dispersed Liquid-Liquid Flow in a Horizontal Pipe. AIChE Journal, 2011, 57 (5), pp.1119 - 1131. ⟨10.1002/aic.12334⟩. ⟨hal-01519714⟩