Flame quenching mechanism velocity

To understand the mechanism of flame quenching in narrow channels in detail, one should first examine the data of flames in mixtures of constant composition, but in charmels of different sizes (Figure 6.1.2). The measured propagation velocities in stoichiometric propane/ air mixture are shown in Figure 6.1.2a. For channel widths slightly larger than the quenching distance, the... 

In Chapter 6.4, J. Chomiak and J. Jarosinski discuss the mechanism of flame propagation and quenching in a rofating cylindrical vessel. They explain the observed phenomenon of quenching in ferms of the formation of fhe so-called Ekman layers, which are responsible for the detachment of flames from the walls and the reduction of fheir width. Reduction of the flame speed with increasing angular velocity of rofation is explained in terms of free convection effects driven by centrifugal acceleration. 

Mechanisms of Flame Stabilization. CRITICAL BOUNDARY VELOCITY GRADIENT. A flame stabilized at the port of a Bunsen burner does not actually touch the rim. There is a dark region, called the dead space, between the rim and the flame. Heat is removed and free radicals are destroyed by the solid surface the burning velocity is reduced to zero and the flame is quenched. Even beyond the dead space, where the flame is able to exist as a luminous reaction zone, the burning velocity only gradually rises to the value achieved at a distance from solid surfaces. 

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