Research on catalytic combustion of low concentration methane in combustion channel of compact reformer

摘要

The combustion channel of compact methane reformer includes fuel flow duct, porous layer and solid connector. There are heat transport and multi-component species diffusion/convection processes in porous structure. The transfer processes are coupled with methane catalytic combustion, and affect the performance and stability of reformer. A 3D in-house code has been developed to simulate the mass and heat transfer processes involving chemical reactions in the reformer channel in specific condition (mass fraction of CH_4 Y_(CH_4) is less than 1% in the mixture of methane and air). It shows that, catalytic combustion reactions mainly tack place on the porous layer near inlet with a higher temperature area, the biggest heat flux region from the bottom wall is found near the higher temperature area. The reaction rate of methane, temperature of porous layer and heat flux increase with the increase of Y_(CH_4). In general, 0.4% is an adequate value for Y_(CH_4). The research has a benefit meaning to provide a guideline for the improvement and design for compact methane reformer.