Velocity Field Structure and Flocculation Efficiency in Taylor-Couette Flow

Abstract

Velocity field data were acquired for Taylor-Couette flow in the annulus gap between a rotating inner cylinder and a fixed concentric outer cylinder by using particle image velocimetry. The flocculation efficiencies were also obtained in the same Taylor-Couette flow under the conditions corresponding to the velocity field measurement. The flocculation efficiencies reached the maximum values due to the closed vortices, their contraction and expansion with time in wavy vortex flow. But out of the wavy vortex flow range, the comparatively low flocculation efficiencies were obtained due to the no-closed vortices which connected with each other.

Keywords:

• flocculation
• PIV
• Taylor-Couette flow
• velocity field structure

ACKNOWLEDGEMENTS

We thank the National Natural Science Foundation of China (No. 50878102) for financial support.