Experimental and numerical investigation of flow field and oxy-methane combustion characteristics in a low-power porous-plate reactor

This study investigates experimentally and numerically the laminar flow field and oxy-methane combustion characteristics in a face-to-face two-porous-plates reactor over wide range of operating global equivalence ratio. The reactor is of low power to mimic the operation of high-temperature membrane reactors (HTMRs), but under sufficient oxygen permeation flux for combustion. This is achieved by using porous plates instead of low oxygen separation rate membranes. Mixture of methane and CO₂ is introduced to the reactor in the channel between the two porous plates and the oxygen is permeated through the plates. The cold flow (non-reacting) characteristics under oxygen permeation are investigated experimentally using particle imaging velocimetry (PIV) system over a range of equivalence ratio, typically 0.4, 0.5 and 0.6. The data are compared with the numerical results and showed good agreement. Reacting flow field and oxy-methane combustion characteristics, in terms of flow mixing, flame location with respect to the porous plate and species distributions, are investigated numerically over a range of equivalence ratio, from 0.4 to 1.0. The results support the operation of the reactor under stoichiometric condition from performance point of view, especially when the case is projected on the HTMR operation.