固体氧化物燃料电池复合阳极管道由多孔层、燃料气体通道以及固体平板组成。在多孔层内部,存在着传热、多组分对流/扩散等多种传递过程,它们与CH4的重整反应,CO、H2的电化学反应耦合在一起,既受到设计参数,如孔隙率等的影响,同时对电池性能以及稳定性产生重要影响。编制了三维模拟程序,对阳极复合管道的化学反应以及气体流动、传热过程等进行了研究。研究结果显示,随着孔隙率的增大,在多孔层的较深区域内,重整与变换反应速度明显增加,受它的影响,H2浓度与多孔层温度也相应提高。因此,在一定范围内提高多孔介质的孔隙率对阳极的各种传递过程与化学/电化学反应具有积极影响。
The composite anode duct of solid oxide fuel cell consists of a porous layer,fuel gas flow duct and solid plate.There are various transport processes appeared,such as heat transfer and multi-component species convection/diffusion in the porous layer.Coupled by CH4 reforming reactions and CO,H2 electrochemical reactions,they affect the overall performance and reliability of SOFC.Meanwhile,they are influenced by design parameters,such as porosity of porous layer and so on.By three dimensional CFD approach,the reacting gas flow and heat transfer processes of anode composite duct were numerically studied.It is revealed that when porosity increased,the steam reforming and water-shift reaction rates increase in a thick region of the porous layer,which led to increasing concentration of hydrogen and higher maximum temperature in the porous layer. For the studied parameters,high porosity of the porous layer under proper conditions is beneficial for transport processes and chemical/electrochemical reactions.