The flow regime in a microbial fuel cell is important for multiple reasons. For example, biofilm thickness and substrate supply are influenced by the velocity of the liquid flow through the chamber and over an anode, which in turn determines power output. This study presents the correlation of the results of computational fluid dynamics simulation and electrochemical data of tubular air diffusion microbial fuel cells. A finite volume analysis approach is used to simulate fluid dynamics in a very complex geometry to calculate velocity profiles around individual fibers of graphite fiber brush. From these profiles, the theoretical boundary layer thicknesses are determined to be between 140 and 240 μm for flow rates between 0.01 and 10 mL min⁻¹. The power output was measured at different external resistances and the average power densities were correlated to the boundary layer thicknesses. The power density reached a maximum of 94.7 ± 12.8 mW m⁻² under constant and 81.6 ± 8.4 mW m⁻² under shifting polarization at 1 mL min⁻¹ at the lowest boundary layer thickness of 152 μm.

由于多种原因，微生物燃料电池中的流动状态很重要。例如，生物膜的厚度和基质的供应受流过腔室并流过阳极的液体速度的影响，而液体的速度又决定了功率输出。这项研究提出了管状空气扩散微生物燃料电池的计算流体动力学模拟结果与电化学数据之间的相关性。有限体积分析方法用于模拟非常复杂的几何形状中的流体动力学，以计算石墨纤维刷各个纤维周围的速度分布。根据这些曲线，对于流速介于0.01和10 mL min ^-1之间的情况，理论边界层厚度被确定为140和240μm之间。在不同的外部电阻下测量了功率输出，并且平均功率密度与边界层厚度相关。最低边界层厚度为152μm时，功率密度在恒定下达到最大值94.7±12.8 mW m ^-2，在移动极化下在1 mL min ^-1下达到81.6±8.4 mW m ^-2。