Water Management Simulation of Proton Exchange Membrane Fuel Cells with Micro-ribs Based on Volume of Fluid Model
Abstract
Removal of liquid water from the surface of the gas diffusion layer (GDL) in the flow channel is an effective method for water management in a proton exchange membrane fuel cell (PEMFC). To enhance the water removal, we modify the conventional flow channel by adding a micro-rib in it. Numerical simulations are conducted to explore the water behaviors in the modified channel and the output performances of PEMFCs. The height and width of the micro-rib, as well as the wall contact angles, are investigated through the volume-of-fluid method to optimize the micro-rib. The results exhibit that the micro-rib can remove the liquid water from the GDL surface by the capillary effect when its height is 0.6 mm, width is 0.3 mm, and its contact angle is lower than the GDL surface. Besides, output performances of PEMFCs with the conventional channel and the modified channel are investigated through PEMFC simulations. The results exhibit that the modified channel can improve the output performance of PEMFC by enhancing the oxygen diffusion efficiency. Therefore, the modified channel is a superior alternative to the conventional channel for high output PEMFCs.