Numerical Simulation of Colorless Distributed Combustion with LES/FMDF

\textbf{Honoring Ted O'Brien. }Turbulent mixing and combustion in non-premixed and premixed Colorless Distributed Combustion (CDC) systems are studied with the hybrid large eddy simulation/filtered mass density function (LES/FMDF) methodology and its Eulerian--Lagrangian computational solver. The CDC has shown to significantly reduce NOx and hydrocarbon emissions while improving the reaction pattern factor and stability with low pressure drop and noise. The combustion in CDC is distributed and is characterized by wide fluctuations in flow variables. In addition to non-conventional distributed turbulent reaction, mixing between fuel, oxidizer, and combustion products in CDC is unique and complex. The LES/FMDF model is shown to be able to capture all the unique features of turbulent mixing and combustion in CDC. The consistency of the Eulerian and Lagrangian parts of LES/FMDF is established for both non-reacting and reacting conditions. The LES/FMDF results are shown to be in good agreement with the available experimental data. The numerical results indicate that the variations in the inflow air temperature, jet velocity and composition and premixing have a significant effect on the flow, mixing and combustion in the CDC. They also indicate the importance of jets setup in the combustor.