Measurements of Normal Burning Velocities and Flame Temperatures of Bunsen Flames

Abstract

Stroboscopically illuminated particle tracks are used to accurately measure normal burning velocities of laminar flames. The precision of the measurements is increased by the use of a constant‐velocity profile nozzle which gives a straight‐sided Bunsen cone. Normal burning velocity data are presented for 3.7 to 5.3 percent propane‐air mixtures. The value for the stoichiometric flame was determined to be 44.8 cm/sec. From stroboscopic and streak photographs of particle tracks it is possible to obtain the maximum flame temperature and temperature distribution in the flame front. Measurements from the two types of photographs are combined with the equation of continuity and the equation of state to obtain the flame temperature. The flame temperature for a stoichiometric propane‐air flame was determined to be 2220°K. An extension of this method is used to obtain an approximation of the temperature distribution in the flame front.