摘要
采用分形理论中的重要参数分形维对质子交换膜燃料电池(PEMFC)扩散层的微结构特征进行描述。通过扫描电子显微镜(SEM)采集了TGP-H-060型碳纤维纸和聚四氟乙烯(PTFE)处理过的TGP-H-060型碳纤维纸的平面图像。采用盒维法分别测定了扩散层不同结构特征体:固体骨架、孔隙及两者间界面的分形维。结合盒维法计算原理,研究了三个特征体分形维之间的关系。研究结果表明,当试样孔隙率大于0.5时,孔隙的盒维数大于固体骨架的盒维数,大于两者间界面的盒维数。通过分析可知,用分形维来刻画扩散层(多孔介质)的微结构特征是合理的。可以考虑将分形理论应用到质子交换膜燃料电池建模过程中,使得仿真计算结果更接近实际情况。
Microstructure properties of gas diffusion layer （GDL） in PEM fuel cells were described by fractal dimensions in fractal theory. Scanning electron microscope （SEM） images of TGP-H-060 carbon paper and TGP-H-060 carbon paper treated with poly tetra fluoro ethylene （PTFE） were gathered. Using the box-counting method, fractal dimensions of different GDL structural features were measured： solid matrix, pores and the interface between them. And their relationship was also studied by the computational mechanism of the box-counting method. It＇s found that box-counting dimension of pores is greater than that of solid matrix, and they are all greater than that of the interface. And it＇s reasonable to use fractal dimension to represent microstructure properties of GDL. Fractal theory could be applied to modeling of PEM fuel cells to make the simulation results more approach to the reality.
出处
《电源技术》
CAS
CSCD
北大核心
2006年第6期458-460,共3页
Chinese Journal of Power Sources
基金
教育部高等学校博士学科点专项科研基金(20030497012)
湖北省自然科学基金(2003ABA088)
关键词
气体扩散层
分形维
孔隙
骨架
界面
GDL
fractal dimension
pore
solid matrix
interface
