质子交换膜燃料电池三维气液两相流数值模拟

质子交换膜燃料电池液态水的生成和传输过程研究,是进行电池水管理的关键。该文基于多相混合流理论,建立了质子交换膜燃料电池三维气液两相流动与传热的数学模型。该模型不仅能模拟燃料电池内部反应气的流动、扩散和化学反应过程,还能模拟液态水的传输和相变过程。应用该模型模拟了电池内液态水的分布及其对燃料电池性能的影响,结果表明液态水主要分布在阴极侧,在大电流密度下,液态水阻碍了氧的扩散过程,导致电池性能下降。模拟结果与实验结果吻合较好。

Numerical simulation of three dimensional gas/liquid two-phase flow in a proton exchange membrane fuel cell

Management of the formation and transport of liquid water in proton exchange membrane fuel cells(PEMFCs is crucial for fuel cell operation.A three dimensional gas/liquid two-phase flow and heat transfer model was developed based on multiphase mixture theory.The model includes the reactant gas flow,gas diffusion,and chemical reactions as well as the liquid water transport and phase change processes.The simulations analyzed the liquid water distribution and its effect on the PEMFC performance.The results show that the liquid water is distributed mostly in the cathode and that the cell performance would decrease quickly at high current densities due to obstruction of the oxygen diffusion by the liquid water.The simulation results agree well with experimental data.