Electrochemical mass transfer at a heated electrode in a vertical annular flow cell

Mass transfer data for the simulation of high-speed wire plating with simultaneous heat transfer was carried out in an axisymmetrical tubular flow cell with developing laminar flow mass transfer characteristics. Current–potential curves for ferricyanide ion reduction at different flow rates showed well-defined plateaux. At low flow rates and depending on ΔT, the interaction between forced and concentration driven natural convection was evident, with the latter effect dominating. At higher flow rates, forced convection became dominant. A plot of limiting current against cathode tube temperature at different Reynolds numbers showed an increase in mass transfer with flow rate with data tending to converge at higher temperatures for all flow rates. Data were compared with those of other workers for mass transfer, and also with the analytical Leveque solution for an annular duct and produced reasonable agreement. Data for heat transfer showed a pronounced effect of thermally driven natural convection at lower Reynolds number, but progressively merged with the Leveque solution at higher Reynolds number.