A Three-Dimensional Two-Phase Model for a Membraneless Fuel Cell Using Decomposition of Hydrogen Peroxide with Y-Shaped Microchannel

A three-dimensional, two-phase, multi-component mixture model in conjunction with a finite-volume-based computational fluid dynamics (CFD) technique is applied to simulate the operation of membraneless fuel cell with Y-shape channel. Hydrogen peroxide is employed both as fuel and oxidant, which are dissolved in diluted sodium hydroxide and sulfuric acid solutions, respectively. Almost all transport phenomena occurring in the fuel cell such as fluid flows, mass transport, electrochemical kinetics, and charge transport are accounted in this model. The oxygen O2 gas, which is a product on the anode electrode, is assumed to be insoluble. The presence of gas phase acts to prevent the processes of reactant supply and product removal. Thus, the cell performance is hindered, while it is operated at the normal current density situation. On the other hand, the capillary action is found to enhance the electrolyte transport in the anode porous electrode, which may slightly improve the cell performance at the high-current density situation. Besides, a secondary vortex flow is induced due to the transportation of the gas phase, which drifts from the bottom to the top of the channel. The mixing zone is then inclined, which may result in serious fuel crossing phenomenon.