Predicting the Excess Air Ratio in Industrial Porous Media Burners to Increase the Temperature and Reduce the Emission of NO Using the Method of NSGA-II

In this paper, an approach for the optimization of the porous media burner operation by changingthe excess air ration is presented. For this purpose, a two-dimensional axisymmetric numerical modelfor premixed methane-air combustion in porous media has been developed and multi-step mechanismshave been used. This model solves the continuity equation, momentum equations, the solid and gas phaseenergy and the chemical species transport equations by using the finite volume method. The pressureand velocity have been coupled with the SIMPLE algorithm. The purposes of this paper is to determinethe excess air ratio as design variable so that NO production be at its lowest level or be less than anacceptable certain amount, and the burner temperature to be at its highest level using the NSGA-IImethod. The goal of multi-objective optimization is to find a set of possible solutions. The results showedthat by increasing the excess air ratio to ۱.۷, the NO emission will be at its lowest level and, thetemperature is at the highest level for excess air ratio ۱.۵. The excess air ratio of ۱.۶ is selected as theoptimal value at which the NO emission rate and the burner temperature are at the acceptable value.

Keywords:

porous media burner , axisymmetric combustion , multi-objective optimization , emission of pollutant , Non-Dominated Sorting Genetic Algorithm