Laminar, turbulent, and inertial shear-thickening regimes in channel flow of neutrally buoyant particle suspensions

Laminar, turbulent, and inertial shear-thickening regimes in channel flow of neutrally buoyant particle suspensions

Lashgari, I.
Picano, F.
Breugem, W.P.
Brandt, L.

Mechanical, Maritime and Materials Engineering

Process and Energy

2014-12-17

The aim of this Letter is to characterize the flow regimes of suspensions of finite-size rigid particles in a viscous fluid at finite inertia. We explore the system behavior as a function of the particle volume fraction and the Reynolds number (the ratio of flow and particle inertia to viscous forces). Unlike single-phase flows, where a clear distinction exists between the laminar and the turbulent states, three different regimes can be identified in the presence of a particulate phase, with smooth transitions between them. At low volume fractions, the flow becomes turbulent when increasing the Reynolds number, transitioning from the laminar regime dominated by viscous forces to the turbulent regime characterized by enhanced momentum transport by turbulent eddies. At larger volume fractions, we identify a new regime characterized by an even larger increase of the wall friction. The wall friction increases with the Reynolds number (inertial effects) while the turbulent transport is weakly affected, as in a state of intense inertial shear thickening. This state may prevent the transition to a fully turbulent regime at arbitrary high speed of the flow.

http://resolver.tudelft.nl/uuid:1d714332-1b46-4c7b-b3d2-b36b8f1c848e

https://doi.org/10.1103/PhysRevLett.113.254502

American Physical Society

0031-9007

http://journals.aps.org/prl/abstract/10.1103/PhysRevLett.113.254502

Physical Review Letters, 113 (25), 2014

Institutional Repository

journal article

© 2014 American Physical Society