Mass transfer at the confining wall of a minichannel

Abstract

Experiments were conducted in a 22-cm long minichannel with a cross-section of 3 mm × 3 mm. Copper electrodes 22 in number were arranged in line with the inner surface of the minichannel. A fluid electrolyte belonging to ferri-ferro redox system is selected as liquid phase. Nitrogen acted as the gas phase. Limiting current is obtained at the point electrodes for an electrochemical redox reaction. Mass transfer coefficient is calculated from this limiting current value. Reynolds number for the liquid was varied in the range of 2820–12692. The flow systems considered were homogeneous flow and gas–liquid flow. In case of homogeneous flow, the mass transfer coefficient increased with liquid velocity whereas for the case of gas–liquid flow, the mass transfer coefficient decreased with both liquid and gas velocities. Correlation equations were obtained for both the flow systems by using least squares regression analysis.[copyright information to be updated in production process]