Performance of a PEM fuel cell with oscillating air flow velocity: A modeling study based on cell impedance

Andrei Kulikovsky

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arXiv · 2008.07101

Performance of a PEM fuel cell with oscillating air flow velocity: A modeling study based on cell impedance

Andrei Kulikovsky

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Abstract

A model of PEM fuel cell impedance is developed taking into account imposed harmonic perturbation of the air flow velocity in the cathode channel. The flow velocity modulation with the amplitude proportional to AC amplitude of the cell potential lowers the resistivity $R_h$ due to oxygen transport in channel. When relative amplitudes of velocity and potential oscillations are equal, a complete compensation of $R_h$ occurs. This effect explains experimental findings of Kim et al. (doi:10.1016/j.jpowsour.2008.06.069) and Hwang et al.(doi:10.1016/j.ijhydene.2010.01.064), who demonstrated significant improvement of PEM fuel cell performance under oscillating air flow velocity.

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Andrei Kulikovsky. 2020-08-17. Performance of a PEM fuel cell with oscillating air flow velocity: A modeling study based on cell impedance. https://arxiv.org/abs/2008.07101

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