A simple model of fuel spray burning

摘要

In 1978, Samson et al. published two papers [1,2] on the burn-ing of fuel sprays, in particular on competitive effects between burning droplets in dense fuel sprays. In Ref. [2] this model was ap-plied to experimental test data due to Nuruzzaman et al. [3]. The comparison of the model with the test data turned out to be disap-pointing. The model indicated a rather steep dependence of the burning rate on the interdroplet distance, while the test data were insensitive to the interdroplet separation. We have recently found a flaw in Ref. [2], which is corrected in the current publication.rnIn [2] interdroplet distances were calculated by assuming decel-eration of droplets with a given initial velocity due to Stokes drag. The gas viscosity was assumed to be that of air at room tempera-ture. In reality, the viscosity of the flue gas around the burning droplets must be considerably larger than that of ambient air on account of the high temperature in the flame zone. This leads to much quicker deceleration of the droplets, hence to much smaller interdroplet distances and consequently to much smaller burning rates than in our previous calculations.