Study on the effect of temperature on pressure drop and under-rib convection in PEMFC

ABSTRACT

Pressure drop effectively reflects the state of water in PEMFC channels and gas diffusion layers. In order to study the regularities in pressure drop and the characteristics of the under-rib convection in the PEMFC at different temperatures, a three-dimensional multiphase flow model was presented, which considers the formation and transport of water inside the cell, as well as the mechanisms governing the conversion between different states of water (liquid water, water vapor and membrane water). The model was imported into Fluent using user-defined functions to simulate and analyze under-rib convection characteristics within the fuel cell at different temperatures. A fuel cell testing system was established to perform tests on polarization curves and anode pressure drop at different temperatures. The results show that the model agrees well with the experiment data, with a maximum error of 5.34%. The anode pressure drop shows a step-level characteristic with three segments: a normal segment, an increasing segment and a stepped segment. As the temperature increases, both the average anode pressure drop and the velocity vector of reactants gradually increase. Notably, the peak velocity vector is observed in the rib-turning region, where heightened under-rib convection is evident.

KEYWORDS:

• PEMFC
• pressure drop
• under-rib convection
• computational fluid dynamics
• water management

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

The data that support the findings of this study are available from the corresponding author, YF L, upon reasonable request.

Additional information

Funding

The work was supported by the State Key Laboratory of Automotive Safety and Energy [No. KFY2218]; the National Natural Science Foundation of China [No. 52376091]; the State Key Laboratory of Engines (Tianjin University) [No. K2023–04].