Simulation study on PEM fuel cell gas diffusion layers using x-ray tomography based Lattice Boltzmann method

摘要: The Polymer Electrolyte Membrane (PEM) fuel cell has a great potential in leading the future energy generation due to its advantages of zero emissions, higher power density and efficiency. For PEM cell, Membrane-Electrode Assembly (MEA) is key component which consists membrane, two catalyst layers gas diffusion (GDL). success optimum output relies on mass transport electrode especially cathode side. carbon based GDL one most important components since it basic roles providing path ways for reactant gases layer as well excess water removal. A detailed understanding visualization from micro-scale level limited by traditional numerical tool such CFD experimental methods complex geometry porous structural. In order take actual information into consideration, x-ray tomography technique employed able reconstructed structure paper or cloth GDLs three-dimensional digital binary image can be read directly LB model carry out simulation. This research work contributes develop combined methodology single phase Lattice Boltzmann (LB) simulation. This newly developed demonstrates capacity simulating flow characteristics phenomena media dealing with collision particles at pore-scale. results reveal heterogeneous nature structures influence transportation reactants terms physical parameters porosity, permeability tortuosity. compression effects have been investigated. show that c applied pressure will negative average pore size, porosity through-plane permeability. range suggested gives in-plane one-dimensional oxygen partial pressures main direction studied low, medium high current densities. It s observed drop across increase increasing pressure. Key Words: GDL, simulation, SPSC, SPMC, tomography, paper, cloth, permeability, degree anisotropy, tortuosity, transport.