Effects of reaction chamber geometry on the performance and heat/mass transport phenomenon for a cylindrical methanol steam reformer

This study utilizes the SIMPLE-C algorithm and Arrhenius form of reaction model to simulate the three-dimensional laminar flow field and the reaction in a cylindrical methanol reformer under steam reforming. Then the effect of geometrical and thermo-fluid parameters on the heat and mass transfer, the methanol conversion as well as the performance of hydrogen production in a cylindrical methanol reformer with a specified volume of catalyst bed will be investigated in the present study. The results indicate that the smaller diameter-to-length ratio (D/L) of reformer with a larger catalyst bed thickness (LCB) enhances the methanol conversion and hydrogen production, in which, the best methanol conversion efficiency of 85.49% and hydrogen concentration of 48% (in wet base) were obtained at LCB = 15 mm (D/L = 0.08), porosity ε = 0.3, and wall temperature equal to 300 °C. Furthermore, the increase of the inlet fuel temperature improves the hydrogen production. That is, when the inlet temperature is 140 °C, high hydrogen concentration of 55% (in wet base) of was achieved.

► A model is to simulate the reaction in a methanol reformer by steam reforming. ► The methanol conversion and hydrogen production are investigated. ► A thicker catalyst bed enhances the methanol conversion and hydrogen production.