S054021 Effect of unstable flow of polymer solution on mixing in micro channels

Abstract

In this study, we have investigated the mixing property of water and polymer solution in micro-channels. We have utilized T-shaped micro-channels which have contraction-expansion parts with five asymmetric rectangular block gates and observed the mixing procedure. Dyed water and a dilute aquaus solution of polyethylenoxide (PEO) of 100 ppm by weight were mixed in the tests. In the micro-channels, the polymer solution caused unstable vortexes before the rectangular gates and the instability of the flow grew at the later part of the contraction-expansion region. The unstable flow with the vortex due to the elastic property of the polymer solusion leaded the efficient mixing.