Background

While numerical simulations of turbulent fl ows applying Reynolds averaging techniques sol-ve equations for ensemble or time averaged mean quantities, large-eddy simulations (LES) have the capability of resolving the major part of the turbu-lent kinetic energy. Hence, only the infl uence of the small turbulent scales on the resolved fi eld has to be modeled. Since, in addition, the small turubulent scales fulfi ll the common modeling assumption of isotropy much better then the large scales, a very high accuracy in predictions of the turbulent fl ow fi eld can be achieved by using LES. This is particulary interesting for simulations of chemically reacting fl ows, where an accurate description of mixing is essential and very complex phenomena like turbu