Fuel cell systems based on liquid energy carriers have great potential to be established in the market without the necessity of a hydrogen infrastructure. Especially the usage of fuels with an existing infrastructure like diesel allows an early breakthrough of the technology. In the framework of the development of a diesel fuel processor for PEM fuel cells, this paper presents the results from the ongoing optimisation of a microchannel heat changer for diesel steam reforming. Four downscaled reformers with different noble metal catalytic coatings were operated in order to identify the most favourable catalyst formulation. Diesel surrogate was processed at varying temperatures and steam-to-carbon ratios. The reformer performance was investigated considering reformate composition, fuel conversion, and deactivation from carbon formation. Complete fuel conversion was obtained with several catalysts. One catalyst in particular was less susceptible to carbon formation and showed high selectivity. A fifth downscaled reformer was implemented with an increased channel height in order to optimise the reformer geometry. In operation the reformer showed advantages in performance and pressure loss in comparison to the original channel height. Within the reformer optimisation, CFD modelling of the downscaled reformer is carried out. An existing CFD model was applied for the computation but showed deviation from measurements. Therefore, a new approach for CFD modelling the downscaled reformer is introduced.
展开▼
