4.4. Stability Limits of Laminar Flames

There are two types of stability criteria associated with laminar flames. The first is concerned with the ability of the combustible fuel–oxidizer mixture to support flame propagation and is strongly related to the chemical rates in the system. In this case, a point can be reached for a given limit mixture ratio in which the rate of reaction and its subsequent heat release are not sufficient to sustain reaction and thus propagation. This type of stability limit includes (1) flammability limits in which gas-phase losses of heat from limit mixtures reduce the temperature, rate of heat release, and the heat feedback, so that the flame is not permitted to propagate; and (2) quenching distances in which the loss ...

Get Combustion, 5th Edition now with O’Reilly online learning.

O’Reilly members experience live online training, plus books, videos, and digital content from 200+ publishers.