Abstract Scaling up of microbial fuel cells is a challenge for practical applications in wastewater treatment. In addition, the flow control is an important aspect for the electrochemical reactions occurring at the electrodes are influenced by fluid motions. By using dimensionless parameter analysis fluid regimes can be investigated in different scales of reactors. In this study, four important dimensionless flow parameters such as Reynolds number, Peclet number, Schmidt number, and Sherwood number were used for systematic analysis of hydrodynamic effects and power performance of recirculation mode microbial fuel cells together with computational fluid dynamics method. Results showed that the higher value of Reynolds number enhanced the convective flow of anolyte due to the dominant inertial forces in the flow field. Therefore, Reynolds number of 1.6 × 101 were obtained high mass transfer coefficient of 4.76 × 10−7 m s-1 and thin diffusion layer thickness of 2.52 × 10-3 m. Maximum power density and limited current density of 2422.8 mW m-2 and 4736.4 mA m-2 were obtained respectively which were higher than Reynolds number of 0 by 1.61 and 1.69 times. These findings shall be useful for effective recirculation flow mode MFCs power production and have a great possibility for large scale applications.

中文翻译：

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应用在循环微生物燃料电池中的主导流动参数

摘要 微生物燃料电池的放大是废水处理实际应用的一个挑战。此外，流动控制是发生在电极处的电化学反应受流体运动影响的一个重要方面。通过使用无量纲参数分析，可以在不同规模的反应器中研究流体状态。本研究利用雷诺数、佩克莱特数、施密特数和舍伍德数等四个重要的无量纲流动参数，结合计算流体动力学方法，系统分析了循环模式微生物燃料电池的水动力效应和动力性能。结果表明，由于流场中占主导地位的惯性力，较高的雷诺数值增强了阳极电解液的对流流动。所以，雷诺数为 1.6 × 101，获得了 4.76 × 10-7 m s-1 的高传质系数和 2.52 × 10-3 m 的薄扩散层厚度。获得的最大功率密度和极限电流密度分别为2422.8 mW m-2和4736.4 mA m-2，比雷诺数0高1.61倍和1.69倍。这些发现将有助于有效的再循环流动模式 MFC 发电，并具有大规模应用的巨大可能性。