Pressure drop

Stoichiometry

Chemistry

Materials science

Chromatography

Physics

Proton exchange membrane fuel cell

Flow (mathematics)

Two-phase flow

Organic chemistry

Membrane

Mechanics

Physical chemistry

Thermodynamics

Analytical Chemistry (journal)

Phase (matter)

Cathode

Biochemistry

Energy

The aim of this study is to improve two-phase flow uniformity of proton exchange membrane fuel cells (PEMFCs) with parallel flow-fields. Therefore, a series of experiments are performed to find the relevance of cathode stoichiometry ratio, unsteady distribution of water coverage ratios and power of a PEMFC with Z-type flow-field. The experimental results indicate that at high cathode stoichiometry ratios, the power and efficiency are stable but their magnitudes are low. In addition, the fuel cell later reaches to its stable power and efficiency. However, the duration of this stability is higher than low cathode stoichiometry ratios. A 3D numerical model is proposed in order to simulate two-phase flow in channels of parallel flow-fields. This model, which is validated by the experimental results, considers the microstructure of gas diffusion layers. By using this model, a modified flow-field with uniform distribution of single-phase and two-phase flow is introduced. Unlike the simple flow-field, the plugs do n...

Numerical and experimental study of two-phase flow uniformity in channels of parallel PEM fuel cells with modified Z-type flow-fields