An Experimental Study on Flame Stability on Wire Meshes

The structure and the flashback critiera of premixed flames of stoichiometric methane-propane-, town gas-and kerosene-air supported on a wire mesh were studied under atmospheric pressure over a wide range of mixture temperature T0 and mass flow rate G by measuring flame and wire mesh temperatures Tf and Tm. It has been found that Tf is determined solely by G regardless of To and wire mesh dimensions. Furthermore, the conditions of flashback to the unburned mixture behind the mesh can be explained by the velocity balance between the burning velocity sum of the imaginary flat flame at temperature Tm and the mean mixture flow velocity Uo, according to: where Km and Kc are the constants characteristic of the mixture strength and the mesh dimensions, respectively. For kerosene- air mixture, the overall activation energy E obtained from the flashback criterion is much smaller than that of normal high temperature flames, which suggests that the reaction processes in the flashback are different from those of normal flames.