Measurements of the combustion characteristics of compound clusters in pressure-atomized spray flame

In order to understand the combustion characteristics of droplet clusters consisting of a number of cluster sizes of i.nhomogeneous droplets, measurements of local chemiluminescence (OH, CH arid C,) were taken simultaneously with measurements of the droplets’ size and velocity in a spray flame stabilized by a recirculating flow. The limitations of using Cassegmin optics to measure chemiluminescence in actual spray flames was investigated. The Cassegrain optics developed were able to detect the local chemiluminescences of OK CH and C, in an actual spray flame. The intensity ratio of the time-averaged local chemiluminescences (&/OH) showed the local equivalence ratio of the fuel droplets in the spray flame. These five signals were analyzed statistically and spectrally, and finally combined to produce cross-correlation coefficients. These data can provide inhormation about the combustion characteristics of droplet clusters. The change in the burning mode of droplet clusters, from external group combustion to internal group combustion, was confirmed experimentally.