On the transport of small bubbles under developing channel flow in a buoyant gas-evolving electrochemical cell

A gas-evolving electrochemical cell with natural convection due to buoyancy is modeled using a hydrodynamic two-phase mixture model. Physical paramete rs are taken from the chlorate process, where hydrogen is evolved at the ca thode. Constitutive closure laws, based on empirical relations developed fo r sedimenting particles, give the motion of the monodisperse gas phase rela tive to the mixture. Typical results display the effect of bubble size, cha nnel width, and current density on the buoyant flow rate of the electrolyte through the channel. Results from the numerical simulations are also compa red to data measured by Boissonneau and Byrne(1) on a cell with gas evoluti on on both the anode and the cathode. Qualitatively good agreement was foun d.