* Department of Mechanical Engineering
** Department of Electrical Engineering
The purpose of this study is to investigate the impact of pulsing reactant flows on the performance of a PEMFC. This study considers a full range of pulsing flows and their effect in power performance over time. Pulsing amplitudes flow rates and pressure for each reactant were kept constant. The factors evaluated were normalized power performance and pulsing frequency of each reactant flow over time. The experiments were performed at lower flow rates and temperatures of reactants than in standard operating conditions. Operating a PEMFC at these conditions allows the study of water accumulation and its removal using pulsing flow of reactant. Power measured under continuous flow rate of reactant flows was used as a baseline indicator. Power performance results were normalized using the highest power value under continuous flow conditions. Pulsing of reactants opens an opportunity as a practical water management procedure. In addition, this technique helps extending power on PEMFC when limited fuel is supplied. The data collected was presented in graphical as well as numerical form.
Keywords: PEMFC, Pusling.
Proton Exchange membrane fuel cells (PEMFC) are considered a clean and alternative form of energy conversion for stationary as well as mobile applications. Issues regarding hydrogen supply as well as water management are still significant factors in PEMFC design. An early model of water generation and its behavior regarding PEMFC channels was discussed by Basu . Further studies of two-phase flow and blockage and their cor...
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