Untitled - Aerobib - Universidad Politécnica de Madrid

Chapter 8
Ignition, flammability and
quenching
8.1 Introduction
In the preceding chapter we have analyzed the properties of a plane wave propagating
in a stationary regime, through an indefinite combustible mixture whose state and
composition are uniform. Although the problem is far from being completely solved,
the essential characteristic of those waves are well understood, and a precise formulation
of the same is available as well as several methods to solve the resulting equations,
including some practical solutions, which may be considered as fairly acceptable when
compared to experimental results.
However, it must be said that the stage of knowledge is not as favorable for
other fundamental questions relative to flames such as: the problem of ignition of
a combustible mixture; the possibility of a flame to propagate through a mixture of
given state and composition; and the influence of the vicinity of the walls on the
characteristics of the flame. Even when a great amount of attention has been applied
during recent years to the study of these problems, the progress achieved, specially
from the theoretical stand-point, has been considerably less than for the case of an
indefinite plane wave, to the extreme that the causes of some of the phenomena are
still unknown as well as their governing laws.
The present chapter contains a brief description of each of the above mentioned
problems, accompanied by a selected bibliography which will enable a more detailed
study on each one.
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