Abstract
For bridging between knowledge on droplet combustion and on spray combustion, the monodispersed suspendeddroplet cluster (MSDC) model with which both the droplet spacing and the initial droplet diameter were well controlled was developed, and combustion behavior of the MSDC models in a high-temperature air were examined under microgravity conditions. When the droplet spacing was in the intermediate range, each droplet was ignited to form an individual flame, which enveloped each droplet, and each flame merged into the group flame. The diameter of the burning sphere decreased at the beginning of combustion, and turned to increase afterward. The transition from the individual flame to the group flame occurred around the time when the burning sphere diameter reached its minimum. The ignition delay and the burning time increased with decreasing the droplet spacing, regardless of the droplet number and the model dimensions.
