NOx Emissions Prediction from a Turbulent Diffusion Flame

Abstract

This work studies the finite volume technique of numerical discretisation by considering a transport process of diffusion. The case investigated is the prediction of NOx emissions from a turbulent diffusion flame arising from the combustion of methane in a cylindrical furnace. A finite volume-based method in a commercial CFD code (Ansys Fluent) was used.This simulation study was done in two and three dimensions. The assumption of constant specific heat resulted to over-prediction of NOx   emissions from the combustion system while the use of variable mixture specific heat gave realistic results for the 2D and 3D simulations. The predicted average exit temperature and velocity of the flue gas were 1780 K and 3.12 m/s respectively for the 2D simulation, and 1800 K and 3.21 m/s respectively for the 3D simulation. The predicted mass fraction of NO pollutant (thermal and prompt) was 0.003311 and 0.004699 for the 2D and 3D simulations respectively.