Flame turbulence interaction in lean premixed flame.

Abstract: Some fundamental physical questions were highlighted through a literature study. The mathematical model for both the initiation of turbulence fields and for the DNS solver was shown. Initial turbulence fields were then formed by the different methods and a comparison between them was made. The comparison included differences in overall pattern through the use of different energy spectrum functions, which also was reviewed in detail. Flame-turbulence interaction for a lean hydrogen-air flame at different turbulence fields, by varying the turbulent intensity and integral length scale and thereby also the Reynolds and Karlovitz numbers, was studied in 2D and 3D through DNS. The phenomenon of preheat zone broadening by turbulent eddies, the distribution of species within the reaction zone and preheat zone, pressure effects on the reaction zone, eddy pair distortion of the flame front and 2D-3D simulation differences were observed qualitatively. Turbulent flame speed, flame induced turbulence and flame surface density was measured quantitatively through defining of the instantaneous flame surface position by the fuel distribution. Based on the used set up, an outlook towards future work was done.