DNS of $H_2$/Air Combustion using Complex Chemistry

Direct numerical simulation (DNS) is used to study reacting, laminar, vortex rings and turbulent diffusion flames. A novel, all--Mach number algorithm developed by {Doom et al} ({\it J. Comput. Phys.} 2007) is used. The chemical mechanism is a nine species, nineteen reaction mechanism for $H_2$ and Air from Mueller at el ({\it Int. J. Chem. Kinet.} 1999) and the extended Zel'dovich mechanism was used to account for the formation of $NO$. Simulations were performed for three dimensional vortex rings where diluted $H_2$ at ambient temperature (300 K) is injected into hot air (1200 K). The effect of Damkohler number and stroke length will be discussed. Simulations of a three dimensional turbulent diffusion flames were performed. Isotropic turbulence is superimposed on an unstrained diffusion flame where diluted $H_2$ at ambient temperature interacts with hot air. Results of the simulation will be discussed.