Prediction of droplet size distribution in sprays of prefilming air-blast atomizers

Abstract

Droplet size distribution is a crucial parameter of atomization process besides droplet mean diameter. In this paper, the finite stochastic breakup model (FSBM) of prefilming air-blast atomization process has been proposed according to the self-similarity of droplet breakup. There are four parameters in FSBM, which are the initial droplet diameter D 0 , the maximum stable droplet size D c , the minimum mass ratio of a sub-droplet to the mother droplet a, and the droplet breakup probability P ( D ) . The simulation results of droplet size distribution with this model agreed well with the experimental results of prefilming air-blast atomizers. With this model, the nonlinear relationship between the mean droplet diameters and droplet size distribution of the air-blast atomization process can be predicted exactly.