Simultaneous measurement of droplet velocity and size and flame mantle temperature by phase Doppler anemometry and two-colour pyrometry

Phase Doppler anemometry and a two-colour pyrometer have been combined to provide simultaneous, local measurements of kerosene droplet velocity and size and temperature of the burning soot mantle. Preliminary measurements within the flame brush that develops in the shear layer of a swirl-stabilized, gas-supported kerosene flame with a swirl number of about 0.19 and potential heat releases of 10.6 and 15.5 kW, respectively, are described. The results show that the maximum burning fraction of the droplets occurs adjacent to the region denoted as gas flame but the value ranges between 20+or-5 and 40+or-5% depending on the axial station, and decreases sharply across the shear layer. The flame mantle temperature was found to be independent of droplet diameter, which agrees with previous results in the literature. The likely experimental errors are assessed in the context of the measurements in the swirl burner.