An Investigation of Pollutants Emission of Methane-Air Combustion in Porous Burners (PBs), from the view point of numerical modeling

Document Type : Research Article

Authors

Abstract

Combustion zone temperature in porous burners (PBs) is lower than free flame burners, which leads to a reduction in NOx emission. Furthermore, because of enough resident time for complete combustion, amount of CO emission will be reduced. In this research, pollutant emissions are investigated for a 5 kW porous burner integrated with a heat exchanger. Navier-Stockes, energy and the chemical species transport equations in a porous media with local thermal equilibrium assumption between the solid and gas are solved. 2D temperature field and species concentrations are presented in the premixed methane - air combustion. The effect of excess air on CO and NO emission are investigated. Results are acceptable with comparison of experimental data, also the results of this simulation are better than some simulations in quantitative and qualitative sense.

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