丁玉杰 Likes:

Impact Factor:

13.3

DOI number:

10.1016/j.cej.2023.143011

Journal:

Chemical Engineering Journal

Key Words:

PEM fuel cell; Scaling analysis; Damkohler number; Flow field; Diffusion–reaction process

Abstract:

Diffusion-reaction coupling process in flow fields dominates the performance of proton exchange membrane fuel cell. This paper defined a new second mechanistic Damkohler ¨ number (DaII,mech) to compare the similarity and efficiency between different flow fields. Dimensionless model and numerical model were combined together to analyze the single channels, parallel and single-serpentine channels. According to trends of DaII,mech curves over current density, the diffusion–reaction interaction can be divided into three states: reaction-enhanced (DaII,mech ~ 1000), transition and diffusion-limited states (DaII,mech ~ 100). With the enlargement of active area, almost the same Damkohler ¨ curves and contours demonstrate the similarity of diffusion–reaction process in single channel and parallel channels. But there is no obvious scaling invariance over active area for single-serpentine channels due to its asymmetric structure. A new efficiency evaluation criterion (EEC) based on Damkohler ¨ number and Euler number is proposed to comprehensively compare the fuel cell performance. The EEC curves also present three-state characteristics. And the EEC values of parallel channels are several orders of magnitude higher than that of single-serpentine channels. This scaling method is expected to be further generalized to other flow fields and operating conditions to accelerate the fuel cell design and optimization.

Indexed by:

Journal paper

Discipline:

Engineering

First-Level Discipline:

Chemical Engineering and Technology

Document Type:

J

Volume:

465

Page Number:

143011

Translation or Not:

no

Date of Publication:

2023-01-01

Included Journals:

SCI