MASS-TRANSFER ENHANCEMENT IN A SYMMETRICAL SINUSOIDAL WAVY-WALLED CHANNEL FOR PULSATILE FLOW

Mass transfer characteristics in a sinusoidal wavy-walled channel are investigated experimentally for pulsatile flow with varying flow parameters, i.e. net flow, amplitude and frequency of fluid oscillation. We show that combination of flow separation and fluid oscillation leads to a significant enhancement in the mass transfer rate under laminar flow conditions. This enhancement is due to rapid fluid mixing induced by the dynamic behavior of the vortex in this channel. The Sherwood number for pulsatile how can be expressed by the following relation: Sh(p)(m) = Sh(s)(m) + Sh(o)(m) where m is the exponent, and subscripts mean s-steady flow, o-oscillatory flow and p-pulsatile flow. Although the value of m depends on the amplitude of fluid oscillation, it becomes constant at large amplitude, i.e. m = 4.