An experimental study was made of the interaction phenomena of droplet array combustion in ambient environments. The droplet, size about 1mm, was supported from a optical fiber and ignited with a hot wire. The droplet temperature, combustion lifetimes and burning rate constants were measured for fuel of n-heptane. Factors investigated include junction spacing, suspender spacing and array configuration.
Results show that the burning process depends on the initial array configuration. The $d^2$-law is found to be correct when applied to both of the droplet in array and the single droplet. For separation distance about 5mm, there exist a critical state. So the transition from a merged flame to separated flames occurs and burning velocity is much faster than before. Combustion lifetime of the lower droplet is shorter than that of the upper droplet through the two-dimensional array combustion. Burning rate constants of the droplets in arrays are smaller than that of the single droplet and increase when separation distance increase. Combustion lifetimes of the droplets in arrays are longer than that of the single droplet and decrease when separation distance increase. After all, we can say that array configuration and the mergedness of the flame are the important factors governing multi-droplet combustion.
