ABSTRACT

A closed-form solution ofEq. (9.128) cannot be obtained. To overcome this difficulty, an approximate method can be introduced by linearizing the around the initial temperature Ti:

and

Using (9. the exponential integral in Eq. 128) becomes

by which the integration of Eq. (9 .128) becomes

0 - RT? CPeE/RT,

E ApcA(-ll.H)

(9.131)

The denominator of the right-hand side of Eq. (9.132) is the charackristic time for the ignition delay:

- RT? ( C"eE/RT, )· td-' E ApcA(-ll.H) 133)

In fact, using td defined by Eq. 133), (9. 32) can be rearranged as

or

(9.135)

which predicts that as t --+ td the critical temperature of the reacting system Tcr goes to infinity, which justifies the definition of fJ by Eq. (9.133).