Numerical Simulation of a Fluidic Oscillator for Water Removal Enhancement in PEM Fuel Cell

The fluidic oscillator is one solution to the problems of water management of the Polymer Electrolyte Membrane Fuel Cell (PEMFC). In low temperature fuel cells such as the PEMFC, liquid water is produced as a byproduct. At low gas flow rates, the water produced has a tendency to plug the reactant supply channels. When the channels are plugged, reactant supply to the catalyst sites is prohibited and results in fuel cell failure. One proposed method of removing a water drop is to oscillate the drop near its natural frequency in order to free it from the substrate. A variety of methods for oscillating the drop are available including mechanical vibrations, acoustic vibrations and flow pulsations. It is the latter method, i.e., use of the fluidic oscillator that is investigated in this study. The purpose of this paper is to use the experimental and numerical techniques to study and simulate a fluidic oscillator so that detail of flow physics inside the oscillator can be realized. Method on how to use the flow field solution to determine the oscillator response frequency is also described. Numerically results of oscillator frequency will be compared with the available experimental data.