College of Engineering

The present study focuses upon the physics of heat and mass transfer processes in a protruded millisecond microchannel reactor, wherein a steam reforming reaction is proceeding and protrusions are used to improve the transport processes involved. Parametric analysis of the reactor system is carried out using a three-dimensional numerical model that is sufficiently detailed to delineate the role of geometric features and operation conditions in reactor performance. Computational fluid dynamics analyses are performed under different sets of circumstances. In analysing the mechanisms involved in the intensified processes, account is taken of the factors that may influence the reactor performance. New insights into the physics of the processes are presented, with recommendations on how to optimize reactor design for better performance. The results indicate that the flow rates and feed compositions must be adjusted as needed to maximize production of hydrogen and minimize pressure drops. Protrusions are very effective in improving the transport processes involved without greatly impairing hydraulic performance. Methanol can be converted effectively to hydrogen due to the successive continuous interruptions in the presence of hemispherical protrusions. Necessary adjustments to the molar ratio of steam to methanol can be made to control the maximum reactor temperature within certain needed limits. Protrusions can be used to improve the conversion and productivity due to enhanced heat and mass transfer, as they behave as a baffle to direct flow of the reforming process flow stream.