Thermal and Start-Up Characteristics of a Miniature Passive Liquid Feed DMFC System, Including Continuous/Discontinuous Phase Limitations

Abstract

The thermal and start-up characteristics of a passive direct methanol fuel cell system are simulated using a numerical model. The model captures both the thermal characteristics of the fuel cell and the passive fuel delivery system using a multifluid model approach. Since the fuel cell is run without any active temperature control, the temperature may rise until the convective and evaporative cooling effects balance the heat produced in the chemical reactions. The cell temperature can vary as much as 20°C, and it is vital to model the thermal effects for accurate results. The numerical model also includes continuous and discontinuous phase limitations, as well as a probabilistic spread of the porous properties. These added physical characteristics qualitatively portray the departure of carbon dioxide from the anode side of the fuel cell.