Results are presented of two-dimensional computations of air-assist fuel injection into engines with bowl-in-piston and bowl-in-head, with and without swirl and for early and late injection but without combustion. The general finding is that swirl tends to destroy the head vortex of the air/fuel jet and results in a faster collapse of the spray cone toward its axis. Faster collapse is also promoted by high density of the chamber gas (e.g. late injection) and bowl-in-head design (limited availability of chamber gas around the spray, presence of walls and delayed influence of squish by the injector). With enhanced collapse, fuel-rich regions are formed around the axis and away from the injector. With reduced collapse, the radial distribution of the fuel is more uniform. Thus swirl tends to lead to both slower vaporization and richer vapor mixtures. Also, with strong swirl the rich mixtures tend to end up by the injector; without swirl, by the piston. However both the local and the global distributions of liquid and vapor fuel are sensitive to a large number of parameters. Thus specific computations must be made for specific engine designs and specific conditions; generalities can be misleading.
Combustion Optimization Computations-Part I: Swirl and Squish Effects in Air-Assist Injection Engines
Sae Technical Papers
International Fuels & Lubricants Meeting & Exposition ; 1992
1992-10-01
Aufsatz (Konferenz)
Englisch
Squish-Swirl And Injection-Swirl Interaction In Direct-Injection Diesel Engines
British Library Conference Proceedings | 2003
|Squish/Swirl and Injection/Swirl Interactions in Direct-Injection Diesel Engines
British Library Conference Proceedings | 2003
|Effects of Swirl and Squish on S.I. Engine Combustion and Emission
SAE Technical Papers | 1977
|Effects of swirl and squish on S.I. engine combustion and emission
Kraftfahrwesen | 1977
|