Abstract

The purpose of this report is to provide a justication for the following modeling assumptions Spatially uniform temperature Neglecting radial eects in the mass and species balances (1-d) Convective ow (neglecting axial diusion for mass and species-balance) Pseudo-steady-state species balances used in our intermediate delity models in [5, 4, 3]. We largely follow the notation in [6], as well as some of the scaling techniques presented there. We assume that we can look sequentially at the assumptions; we rst consider the assumption regarding the uniform temperature for a transient problem without gas ow and steady-state problems with gas ow; we then discuss the mass and species balances used, assuming a uniform temperature. 1 2 Uniform Temperature in the Stack Our models assume a stack with a uniform temperature (reactor, fuel cell and burner share the same temperature). This was motivated by the fact that heat transfer at this scale is quite fast and the micro-