Ricerc@Sapienza

In order to develop better design tools, it is of prime importance to acquire a basic comprehension of flame flow interaction phenomena under the widely variable operative conditions used in practical devices ranging from power generation burners to aeronautical or rocket combustion chambers. Computational Fluid Dynamics (CFD) is a fundamental tool in research by its extreme flexibility and the availability of a wide range of existing models and the ever increasing computational resources with respect to the ex- periments which are by far more expensive. The numerical simulation of a compressible reactive flow, occurring in such devices at typical operating conditions, is still an open problem in the scientific community. The main reason lies in the fact that diffusion, advection, acoustics and chemical reactions introduce a broad range of spatial and temporal scales. In the context of multi-scale phenomena a relatively unexplored subject is the interplay of the hydrodynamic instability, or Darrieus-Landau (DL), in large turbulent pre- mixed combustion. In fact, the intrinsic instability can be modify the flame propagation and morphology. The DL mechanism appears to play a substantial role in premixed turbulent combustion with high pressure condition. The DL mechanism causing modifications of the flame surface area modify the turbulent burning velocity and mean flame brush thickness. Therefore in this project a study about large scale effects on the methane air premixed flames in turbulent regime and for different pressure values are proposed, considering a low Mach approximation (i.e. neglecting the acoustic interaction phenomena) with one step and finite chemistry.