Investigation on Dynamic Water Transport of PEFCs combining Neutron Radiography and CFD Simulation

The dynamic water transport of a polymer electrolyte fuel cell was investigated using neutron radiography and CFD simulation. Different operating conditions with dry and humidified gas supply were analyzed at 0.2 and 0.8 A cm(-2). The regions with liquid water occurrence were identified using CFD simulations and were verified by neutron radiography. Water accumulation at anode was identified, while at cathode side condensate was sufficiently removed. Thus, the experimentally determined specific pressure drop criterion of 20 mbar m(-1) was confirmed for the investigated type of meander-shaped flow field. The observed maximum water thickness was 0.4 mm inside the channel and served as an input for a closer investigation of dynamic water transport using the Volume of Fluid (VOF) model. The water removal capability at anode and cathode were verified with the VOF simulations. The droplet velocity was approximately 44 % / 50 % of gas velocity at anode / cathode for the investigated droplet shapes.