Fluid mixing and mass transfer enhancement in grooved channels for pulsatile flow

Fluid mixing and mass transfer in grooved channels were studied experimentally and numerically for pulsatile flow with varying flow parameters. A particle advection procedure by numerical simulation indicates that vortex dynamics due to time-periodic flows lead to efficient fluid exchange between channel and groove flows. Mass transfer rates were measured by the electrochemical method. The mass transfer enhancement factor increases with the oscillatory fraction of the flow rate, and depends on the net flow rate and oscillatory frequency. II is found that at high Reynolds numbers this factor suddenly increases at a low oscillatory fraction, in contrast to the cases at low Reynolds numbers.