The impact of molecular diffusion on auto-ignition in a turbulent flow

The inclusion of molecular diffusion into the joint-probability density function (JPDF) method requires terms for transport in physical space and mixing composition space. former is typically neglected high Reynolds number flows but becomes important close to surfaces flamelet related reaction-diffusion structures associated with Damköhler numbers. McDermott Pope (J. Comp. Phys., 2007) proposed an explicit addition a term equation sub-grid filtered method. A approach was used by Fiolitakis et al. (Combust. Flame, 2014) JPDF when combined moment based closures. variant here comprehensive C 1 − 2 chemistry featuring 44 chemical species 256 reactions study impact on auto-ignition flame stabilisation well-characterised Cabra burner. It shown that contribution significant at point predictions carbon monoxide and, particular, hydrogen showing marked improvement. Conditional statistics PDF temperature show improvement due increased fuel rich side leading activity. developed viable boundary layers while spatial resolution requirements mean scalar gradients may prove limiting complex flows.