Shiraz University Iranian Journal of Science and Technology Transactions of Mechanical Engineering 2228-6187 39 M2 2015 10 01 A NUMERICAL STUDY OF A THREE-DIMENSIONAL PROTON EXCHANGE MEMBRANE FUEL CELL (PEMFC) WITH PARALLEL AND COUNTER FLOW GAS CHANNELS 309 323 3242 10.22099/ijstm.2015.3242 EN N. Ahmadi Dept. of Mechanical Engineering, Urmia University of Technology, Urmia, I. R. of Iran H. Taraghi Dept. of Mechanical Engineering, Urmia University of Technology, Urmia, I. R. of Iran M. Sadeghiazad Dept. of Mechanical Engineering, Urmia University of Technology, Urmia, I. R. of Iran Journal Article 2014 02 02 Modeling the heat and mass transport in micro channel is being used extensively in researches and industrial applications. The aim is optimizing fuel cell designs before building a prototype for engineering application. In this study, numerical, three-dimensional, single phase computational fluid dynamics model of a proton exchange membrane fuel cell with both the gas distribution flow channels and the Membrane Electrode Assembly (MEA) has been developed. A single set of conservation equations which are valid for the flow channels, gas-diffusion electrodes, catalyst layers, and the membrane region, are solved by finite volume technique. The present simulated straight channels PEMFC model, accounts for major transport phenomena and the performance. Additionally, the effect of reversing the flow direction at cathode side has been investigated to study the fuel cell performance and species distribution. The results showed that, in the PEMFC with the counter flow channels, the output current density has been decreased and also the kind of species distributions has been influenced by this phenomenon. It is very important to model the back diffusion and electro-osmotic mass flux for determination of ionic conductivity of membrane which affects the performance of fuel cell. Finally, the numerical results are validated by available experimental data. https://ijstm.shirazu.ac.ir/article_3242_c89269fc2762f91e097de314707d1e5b.pdf