Air-liquid water transport phenomena in a proton exchange membrane fuel cell cathode with a leaf-like flow field design

Liquid water management is one of the key research topics for the development and commercialization of proton exchange membrane fuel cells (PEMFCs) as it greatly affects their performance and durability. Nature-inspired designs show their prominent characteristics such as low pressure drops and effective fluid distribution. Those designs with branched configurations similar to leaves allow more efficient water management; therefore, provide better fuel cell performance than the conventional ones. The air-liquid water transport phenomena are studied for the first time for a leaf-like biomimetic flow field design with a channel configuration mimicking the branching of veins in leaves. The study is conducted using a 3D two-phase air-liquid flows transient numerical simulation. The simulation utilizes the volume of fluid (VOF) method to track the gas-liquid interface with the validated dynamic contact angle (DCA) model is implemented for better accuracy. The fundamental understanding of the liquid water transportation behaviors inside this type of biomimetic flow field is made. Observations such as the effect of the branching on the liquid water drainage could be used for the improvement of flow field designs. For the given boundary conditions, the liquid amount in the flow field becomes stable at 1.5 x 10(-4) kg after the start-up time, while the pressure drop fluctuates about 3.25 kPa.

Automated summary

Liquid water management is crucial for the performance and durability of proton exchange membrane fuel cells. Nature-inspired leaf-like designs with branching configurations show more efficient water management and better fuel cell performance. Studying air-liquid water transport phenomena in biomimetic flow field designs can provide insights for improving flow field designs.