Advanced computational tools for PEM fuel cell design

On the modeling of water transport in polymer electrolyte membrane fuel cells

“…The two-fluid governing equation for the liquid water transport in the backing layer and gas flow channel is derived from the volume averaged continuity equation, and it has the following form [35,37] ∂ ∂t…”

“…In the porous backing layer, D s and f (s) are derived based on the capillary pressure theory and by applying Darcy's law for both liquid and gas phases, and can be expressed as [35,37] …”

“…Liquid flow in the gas flow channel can be very complicated, depending on the nature of the channel flow. In this study, an approach similar to [35,37] is used which assumes homogeneous mist flow in the channel, the interfacial drag coefficient f (s) is set to be unity [35] and the liquid diffusivity is fixed at an large value. With such specifications, the liquid saturation almost vanishes in the channel.…”

Coupled modeling of water transport and air–droplet interaction in the electrode of a proton exchange membrane fuel cell

“…Thus, the above mentioned coefficients are evaluated assuming that the membrane water content is the average between anode and cathode water contents, which in turn are directly related to the electrodes relative humidity [3]. Furthermore, the potential influence of the liquid water saturation in the GDLs is not taken into account in accordance with the available studies [3][4][5][6][7][8][9]. The parameter A CA is the control surface area and represents the area under the open channel, while A rib is the associated land (or rib) area and is expressed as percentage of the A CA .…”

“…Jiao et al [8] presented a 3D CFD model to investigate the gas and liquid flow fields in micro-channels, considering six cases for the initial liquid distribution. An analogous investigation was carried out by Sui et al [9] but the transport equations were solved also in the electrodes and membrane. Yi et al [10] studied the along-the-channel liquid water profile and relative scaling-up effects.…”