Visualization of Water Behavior in an Operating PEFC by Neutron Radiography

It is important to understand behavior of water which is generated by fuel cell operation to improve pelformance of the fuel cell. Neutron rays are transparent to most of metals and are attenuated by water. Therefore, neutron radiography is suitable to observe the water behavior in the fuel cell. The visualized and measurement results by using new neutron radiography techniques developed for the fuel cell researches were presented. Thmporal quantitative water thickness distributions in a JARI standard cell were measured. A network model was developed to simulate the gas flow velocity and the pressure distribution based on the measured results. Dynamic neutron CT was applied to 3-cell stack based on the JARI standard and the dynamic 3-D water behavior was observed every 15 seconds. The water distribution through plane in MEA and GDL in a small size fuel cell was measured by an imaging system using a bore-scope.