Modelling of Hydrocarbon and Nitrogen Chemistry in Turbulent Combustor Flows Using Detailed Reaction Mechanisms

The description of chemical kinetics in turbulent reactive flows is an important task to improve combustion models. This paper describes the inclusion of detailed chemical reaction mechanisms into the framework of a turbulent flame simulation. Calculations are based on a finite-volume solution procedure including submodels for turbulent flow, combustion of fuel and radiative heat transfer. The interaction of chemical reactions and turbulence is modelled using the Eddy Dissipation Concept (EDC). The basic idea of incorporating the reaction mechanism into the EDC is described. The oxidation of methane is described with a detailed C1/C2 mechanism. The proposed model is applied to a 400kW turbulent diffusion methane flame in a cylindrical furnace. The measured trends in temperature and species concentrations of CH4, O2, CO and CO2 are adequately reproduced by the predicted profiles. To demonstrate the benefits and limits of this approach, the method is applied to predict gas phase reactions of the DeNOx technology ‘reburning’ using methane as reductive, which is applied to a pulverized coal flame. The detailed reaction mechanism of Miller & Bowman [1] is used to describe the nitrogen chemistry. The nitrogen chemistry is calculated decoupled from the hydrocarbon chemistry in a post-processor step. The modelling results are compared to experimental data of a bench scale test facility.