(1972). Interferometric Observation of Turbulent Mass Transfer in Channel Flow

A traveling, dual-beam laser interferometer has been used to investigate mass-transfer boundary layers on planar electrodes in turbulent channel flow. The effect of secondary flows induced near the electrode/electrolyte int rface by small flow obstacles in laminar bulk flow is compared to the effect of turbulent bulk flow produced by high electrolyte flow rates in an obstacle-free flow channel. It is shown that mass-transfer enhancement can be attained more efficiently by the use of small flow obstacles than by the use of high flow velocities. Turbulent fluid flow can often be successfully em-ployed to increase interfacial transport rates in a variety of industrial unit operations. Many electrochemical pro-cesses, such as electrowinning, electrochemical synthesis, and electrodialysis, tend to be rate limited by slow mass transfer. The application of turbulent in place of laminar electrolyte flow in these processes permits higher operating current densities and thereby improves the space-time yield of the electrochemical system. The mos