A transient analysis of a micro-tubular solid oxide fuel cell (SOFC)

A two-dimensional, axisymmetric transient computational fluid dynamics model is developed for an intermediate temperature micro-tubular solid oxide fuel cell (SOFC), which incorporates mass, species, momentum, energy, ionic and electronic charge conservation. In our model we also take into account internal current leak which is a common problem with ceria based electrolytes. The current density response of the SOFC as a result of step changes in voltage is investigated. Time scales associated with mass transfer and heat transfer are distinguished in our analysis while discussing the effect of each phenomenon on the overall dynamic response. It is found that the dynamic response is controlled by the heat transfer. Dynamic behavior of the SOFC as a result of failure in fuel supply is also investigated, and it is found that the external current drops to zero in less than 1 s.