Mass-Transfer Enhancement in a Furrowed Channel with Arc-Shaped Walls for Pulsatile Flow.

Abstract

Flow patterns and mass-transfer characteristics in a channel with arc-shaped walls are investigated experimentally for steady and pulsatile flows. Flow visualizations are performed by the aluminum dust method, and mass transfer rates are determined by the electrochemical method. This channel experiences an earlier transition to turbulence compared with a channel with the sinusoidal walls previously studied. Mass-transfer enhancement depends on the oscillatory fraction of the flow rate and the Reynolds number for net flow ; however, the effect of frequency is weak. The mass-transfer enhancement factor exceeds the value predicted by the quasi-steady model, in the laminar flow regime, but agrees well, in the turbulent flow regime.