Experimental Investigation And Simulation On The Performance Of H₂-Air PEMFC With 3-Channel Serpentine Flow-fields

As a new energy, Proton Exchange Membrane Fuel Cell (PEMFC) has drawn more and more countries' concern. And relevant research achievements have been obtained continuously. At present, research on fuel cell focuses on theoretical studies, such as the experimental research and model building of small-sized monomer cell. Experimental research can detect the apparent performances of a cell, while model building and software numerical simulation can make complement for the subtle changes that are immeasurable in the experiment. A self-built fuel cell, 25 cm2 is used in the experiment, and COMSOL Multiphysics 3.3a is used for numerical simulation. Experiment and relevant analysis on the performances of the three-channel Serpentine Flow Field PEMFC are conducted. An outline of the dissertation is as follows:The experiment indicates: the pressure of working gases have much impact on PEMFC's voltage. Normally, it is enough for voltage requires keeping low pressure and low flow rate. Flow rate of working gases has significant effect on current character; current density rises and then declines, with the increase of air flow. Current density reaches the maximum as the flow rate of hydrogen to air keeping around 1:2.5. Output characteristic of PEMFC is related to its placements. When anode is on top, voltage characteristic is much better; when bottom, current characteristic better. When discharge voltage is above 0.6 V, the cell performs with downstream is better than that with counter flow; when discharge voltage is below 0.6 V, the cell performs with counter flow is better than that with downstream.A cell model with a two-dimension vertical flow field is also established. The numerical computation on the cell model is conducted via COMSOL Multiphysics 3.3a. The result presents that the maximum value of electric current density occurs at the boundary of rib; electric current density at the inlet is larger than that at the outlet; the maximum velocity of gas is up to 0.7 m/s under simulating conditions.