DISRUPTIVE COMBUSTION OF COAL-OIL-MIXTURE DROPLETS.

Theoretical and experimental investigations on the combustion characteristics of a droplet of multicomponent liquid fuel mixed with fine coal particles have been conducted. Two limiting cases of combustion behavior are identified. In the quiescent combustion mode vaporization simulates batch distillation such that all the liquid components are preferentially vaporized, leading to the evantual formation of large coal particle agglomerates which may modify the combustor performance. In the disruptive combustion mode internal boiling of the more volatile components in possible with the coal partiles serving as heterogeneous nucleation sites. The resultant internal pressure build-up leads to perpetual fragmentation of the droplet, and hence may significantly diminish the various heterogeneous effects associated with spray combustion.