Recent Changes - Search:




edit SideBar

Triple flames

Existence of triple flames can explain the flame stabilisation mechanism behind lifted diffusion fla-mes, Chen (2004). A triple flame consists of curved premixed flame front spanning lean to rich fuel composition along the stoichiometric mixture fraction contour with a trailing diffusion flame formed from the excess fuel and oxidiser in the premixed branches, Chen (2004).

Ruetsch et al. (1995) showed that the heat release rate enhances the flame propagation speed. Echekki and Chen (1998) and Im and Chen (1999) explored the effects of heat release, preferential and differential diffusion and chemistry; these studies indicated that heat release was most important parameter in the enhancement of the flame propagation speed. Preferential diffusion accounts for less than 10 % of the flame speed enhancement near the leading edge, but the flame structure is greatly influenced by flame curvature and H2 and the H-radical at the triple point.

Chen and Echekki (2000) studied buoyancy effects in triple flames. Chen and Echekki (2000) con-cluded that buoyancy and heat release have pronounced effect on the flame propagation velocity. The flame shape is significantly affected by buoyancy and the direction of the gravity vector.

Chen, J. H., 2004.
Echekki, T., and Chen, J. H., Combustion and Flame 114:231-245, 1998.
Ruetsch, G. R., Vervisch, L., and Linan, A., Physics of Fluids 7(6):1447-1454, 1995.

<< Free jet laminar and turbulent diffusion flames | Content | Combustion of inhomogeneous mixture in closed vessel and pressure build up >>

Edit - History - Print - Recent Changes - Search
Page last modified on December 10, 2008, at 03:18 PM