Numerical investigation of gas channel
and shoulder size and temperature On Polymer Exchange Membrane Fuel Cell output current density
N. Ahmadi1*, S. Rezazadeh2
1*PhD student, Mechanical Engineering Department, Urmia University of Technology, Urmia, Iran
2 Assistant professors, Urmia University and Urmia University of Technology, Mechanical Engineering Department
* Corresponding author. E-mail: email@example.com
Received: 03 June 2014; revised version accepted:30 July 2014
A comprehensive single phase, 3D computational model was used with a single straight channel geometry for proton exchange membrane (PEM) fuel cells has been developed. The influence of various parameters such as isothermal and non-isothermal cells and the impact of different geometry of the channel with different width of shoulder and also influence of various operating temperature on fuel cell performance has been studied. The validity of the model is assessed by comparing the computed results with experimental data. The comparison shows good agreements between the modeling results and the experimental data. The simulation showed that the rectangular channel cross-section gave higher cell voltages compared with the other channel cross-section. Simulations using different Channel–shoulder width ratios showed that at high operating current densities, ohmic losses significantly increase with decrease of shoulder width. In contrast with a smaller shoulder width facilitates the distribution of reactants and helps to reduce concentration losses. When the operating temperature increases which leads to high ionic conductivity; that’s caused to high current density.
Keywords: PEMFC; Channel geometry; Over potential; Operating temperature.