Measurements of Effective Temperature and Studies with Special Sources

Abstract

In the three preceding chapters, observations on the emission and absorption spectra of normal stationary flames have been described. In this chapter we shall be concerned with additional observations aimed at elucidating the detailed state of the gases in the reaction zone. These will include quantitative measurements on the relative intensities of lines and bands, or on the contours of individual lines, with the results expressed as effective temperatures. The various methods of measuring flame temperatures have been described fully in the recent edition of Flames (Gaydon and Wolfhard, 1970); here the principles of the methods will be referred to only briefly, but results will be given. Other observations in special sources such as flash photolysis, atomic flames and shock tubes, and also tracer observations using stable isotopes for the study of flame spectra, give information about basic chemical processes and excitation mechanisms and are relevant to the understanding of flame spectra. Work on some special flames, such as those supported by fluorine instead of by oxygen, is also valuable for a discussion of the reaction and excitation processes in normal flames and is therefore included here.