### Abstract

A serpentine flow field is commonly used in both fuel cells and redox flow batteries. Accurate prediction of mass transfer in the porous gas/liquid diffusion layer (GDL/LDL) is essential for both flow field design optimization and pressure drop predictions. Darcy's law has been widely used to predict fluid flow through GDL/LDL in fuel cells and flow batteries. However, since the inertial effect is neglected in the Darcy's law, significant errors can arise when it is applied to serpentine flow fields. In this work, dimensional analyses are performed using both the Buckingham Pi-theorem and the analytical models developed earlier based on Darcy's law and modified Darcy's law. From the Pi-theorem, four and five non-dimensional parameters are obtained from the Darcy's law and the modified Darcy's law, respectively. The variations of Darcy's law errors in predicting under-land cross-flow rate with each of the non-dimensional parameters are studied. By comparing the coefficient of each term of the two models, two independent Pi-terms for under-land cross-flow rate are obtained. The criterion for applicability of Darcy's law is developed based on the two Pi-terms. The model predicted errors of Darcy's law compared very well with experimental data, thus further confirms the applicability of developed criterion.

Original language | English (US) |
---|---|

Pages (from-to) | 391-397 |

Number of pages | 7 |

Journal | Journal of Power Sources |

Volume | 412 |

DOIs | |

State | Published - Feb 1 2019 |

### Fingerprint

### Keywords

- Darcy's law
- Dimensional analysis
- Modified Darcy's law
- PEM fuel cell
- Porous medium
- Under-land cross-flow

### ASJC Scopus subject areas

- Renewable Energy, Sustainability and the Environment
- Energy Engineering and Power Technology
- Physical and Theoretical Chemistry
- Electrical and Electronic Engineering

### Cite this

*Journal of Power Sources*,

*412*, 391-397. https://doi.org/10.1016/j.jpowsour.2018.11.071

**Error of Darcy's law for serpentine flow fields : Dimensional analysis.** / Zhang, Xuyang; Zhang, Xu; Taira, Hidetaka; Liu, Hongtan.

Research output: Contribution to journal › Article

*Journal of Power Sources*, vol. 412, pp. 391-397. https://doi.org/10.1016/j.jpowsour.2018.11.071

}

TY - JOUR

T1 - Error of Darcy's law for serpentine flow fields

T2 - Dimensional analysis

AU - Zhang, Xuyang

AU - Zhang, Xu

AU - Taira, Hidetaka

AU - Liu, Hongtan

PY - 2019/2/1

Y1 - 2019/2/1

N2 - A serpentine flow field is commonly used in both fuel cells and redox flow batteries. Accurate prediction of mass transfer in the porous gas/liquid diffusion layer (GDL/LDL) is essential for both flow field design optimization and pressure drop predictions. Darcy's law has been widely used to predict fluid flow through GDL/LDL in fuel cells and flow batteries. However, since the inertial effect is neglected in the Darcy's law, significant errors can arise when it is applied to serpentine flow fields. In this work, dimensional analyses are performed using both the Buckingham Pi-theorem and the analytical models developed earlier based on Darcy's law and modified Darcy's law. From the Pi-theorem, four and five non-dimensional parameters are obtained from the Darcy's law and the modified Darcy's law, respectively. The variations of Darcy's law errors in predicting under-land cross-flow rate with each of the non-dimensional parameters are studied. By comparing the coefficient of each term of the two models, two independent Pi-terms for under-land cross-flow rate are obtained. The criterion for applicability of Darcy's law is developed based on the two Pi-terms. The model predicted errors of Darcy's law compared very well with experimental data, thus further confirms the applicability of developed criterion.

AB - A serpentine flow field is commonly used in both fuel cells and redox flow batteries. Accurate prediction of mass transfer in the porous gas/liquid diffusion layer (GDL/LDL) is essential for both flow field design optimization and pressure drop predictions. Darcy's law has been widely used to predict fluid flow through GDL/LDL in fuel cells and flow batteries. However, since the inertial effect is neglected in the Darcy's law, significant errors can arise when it is applied to serpentine flow fields. In this work, dimensional analyses are performed using both the Buckingham Pi-theorem and the analytical models developed earlier based on Darcy's law and modified Darcy's law. From the Pi-theorem, four and five non-dimensional parameters are obtained from the Darcy's law and the modified Darcy's law, respectively. The variations of Darcy's law errors in predicting under-land cross-flow rate with each of the non-dimensional parameters are studied. By comparing the coefficient of each term of the two models, two independent Pi-terms for under-land cross-flow rate are obtained. The criterion for applicability of Darcy's law is developed based on the two Pi-terms. The model predicted errors of Darcy's law compared very well with experimental data, thus further confirms the applicability of developed criterion.

KW - Darcy's law

KW - Dimensional analysis

KW - Modified Darcy's law

KW - PEM fuel cell

KW - Porous medium

KW - Under-land cross-flow

UR - http://www.scopus.com/inward/record.url?scp=85057316589&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85057316589&partnerID=8YFLogxK

U2 - 10.1016/j.jpowsour.2018.11.071

DO - 10.1016/j.jpowsour.2018.11.071

M3 - Article

VL - 412

SP - 391

EP - 397

JO - Journal of Power Sources

JF - Journal of Power Sources

SN - 0378-7753

ER -