INVESTIGATION OF THE EFFECTS OF POROUS MEDIA AT THE EXIT OF COUNTERFLOW COMBUSTION USING THE LATTICE BOLTZMANN METHOD

摘要

In this study, the lattice Boltzmann method is utilized to investigate the effects of porous medium at the exit of the counterfloxv combustion. Porous matrices with different arrangements are created by scattering solid obstacles inside the flow path. The LBM model is used for simulation of conduction heat transfer between the discrete parts of the porous medium. A single-step chemical reaction is used for modeling of the combustion of propane/air mixture and properties are recorded at the exit of the domain. However, to investigate the effects of porous media on the emission of the intermediate species like CO, a two-step chemical reaction is utilized to model the methane/air combustion. The results show that the presence of the porous media decreases the maximum exit temperature and causes a more uniform temperature profile at the exit compared with results of combustion without porous medium. Also, utilizing porous media reduces the CO and unburnedfuel concentration at the exit and consequently increases the combustion efficiency. Effects of the different porous structure on exit temperature and species concentrations are also investigated in this study.