Two-phase flow simulation of the catalyst layer/microporous layer interfacial wettability in PEMFCs

To address the microscale two-phase flow issues at the catalyst layer (CL)/microporous layer (MPL) interface in proton exchange membrane fuel cells (PEMFCs), the lattice Boltzmann method is used to simulate the liquid water transport at the CL/MPL interface with different wettability. By clarifying the CL/MPL interfacial volume saturation and surface saturation distribution, the effect of CL contact angle on liquid water transport is revealed. The results show that when the CL is hydrophilic, the CL/MPL interfacial water saturation increases as the CL contact angle increases. Oppositely, when the CL is hydrophobic, the CL/MPL interfacial water saturation decreases as the CL contact angle increases. Further, when both the MPL and CL contact angles are 130°, water drainage at the CL/MPL interface performs the best.