A Note on Flame-Length

Abstract

THREE years ago, whilst endeavouring to make use of flame-length as a means of testing the economic values of different qualities of coal-gas by the determination of their specific flame-lengths, I was led to the discovery of some simple relations, the further study of which will perhaps one day help to simplify the theory of flames. By specific flame-length I mean the length of flame of a combustible gas burning in a normal atmosphere at a standard rate through a simple circular orifice under such conditions as to produce a symmetrical, vertical, steady flame capable of being measured. These conditions are not difficult to obtain in the case of coal gas. In fact for a very long time a flame-length test has been in use amongst gas-makers, but as the comparison has not always been made on the basis of volume the results have not always been satisfactory. The system I advocated was that of stating the flame-length for some standard rate. It occurred to me at that time that the flame-length should be proportional to the consumption or rate of issue of the gas. On submitting this theory to experiment I obtained satisfactory evidence that such was the case, as the following table taken at chance from a series of experiments will show:—