Insights on the interaction of serpentine channels and gas diffusion layer in an operating polymer electrolyte fuel cell: Numerical modeling across scales

• 3D Lattice Boltzmann simulation of the flow on cathode side a micro PEFC at wet and dry operating conditions. X-ray tomographic assessment serpentine channel geometry porous structure GDL. A GDL leads to higher magnitude cross-flows under ribs, transferring gas from one straight next. The normalized local accumulated along are substantially in compared In electrochemically cells, rib will receive more O 2 by convection, increasing reaction. Three-dimensional direct numerical simulations were performed for investigating under-laying diffusion layer (GDL) polymer electrolyte fuel cell (PEFC). field comprised three sections two U-turns. was acquired with high-resolution (2.9 ?m) situ measurements an cell. Simulations considered partially saturated conditions, whereby saturation established via produced water. lattice (LB) methodology adopted simulating single-phase (gas) transport actual geometry. global pressure drop dominated turns channel, while drops quite small sections. case, however, mainly dictated neck-shaped passages created large water clusters inside channel. Owing blockage, length, when inlet flow, GDL, reaching values up 45% 18% implications that cell, would (and thus ). creation through enhance performance ribs since not be main driving mechanism oxygen evaporation. analysis indicated field, although designed as serpentine, behaved like half-interdigitated (with 1.5 mm, half-serpentine depending state flooding).