Analysis of spray characteristics of a jet-film injection element based on Voronoi tessellation

The present paper presents a computational study based on a validated Volume-of-Fluid method on the effects of film thickness and film width on spray characteristics for the simplified jet-film injection element with varying mass flow rate conditions. First, the spray characteristics of a typical jet-film collision were analyzed in terms of the spatial distribution of Sauter Mean Diameter and Voronoi tessellation. Both the Voronoi diagram and the Sauter Mean Diameter contour are useful to evaluate the spray characteristics because they show two different aspects of the sprays. Second, the jet-film spray characteristics were analyzed by decreasing either film thickness or film width to change the mass flow rate. The results show that decreasing film width results in approximately insensitive spray angle and improved uniformity of droplet distribution for different throttleable levels. The present computational results verified our design concept that adopting traditional jet-film injection at a large mass flow rate and modified jet-jet injection at a small mass flow rate to maintain good spray performance during the entire throttleable levels.