Comparison of a pseudocontinuous, heterogeneous 2D conductive monolith reactor model to a 3D computational fluid dynamics model

Conductive catalytic honeycombs of a low-void fraction have gained renewed interest for use in the production of bulk chemicals because of favorable heat transfer properties and a low pressure drop compared to fixed-bed reactors. In this work, a pseudocontinuous, heterogeneous 2D conductive honeycomb reactor model is compared to a detailed 3D computational fluid dynamics model for the case of an irreversible, exothermic first order reaction with emphasis on the description of heat transfer. Excellent agreement in terms of maximum temperature and conversion is found for moderate conditions preferable for technical purposes when using the symmetric model for calculation of the effective radial heat conductivity. Deviations of maximum temperatures at harsher conditions are attributed to the use of global heat and mass transfer coefficients in the 1D channel model and the inherent assumption of a radially fully segregated flow in the continuum approach.