Assessment of the Influence of Intake Duct Geometrical Parameters on the Tumble Motion Generation in a Small Gasoline Engine University of Bologna

Format:

Conference/Event

Author/Creator:

Falfari, Falfari, author.

Contributor:

Bianchi, Gian Marco

Brusiani, Federico

Conference Name:

2012 Small Engine Technology Conference & Exhibition (2012-10-16 : Madison, Wisconsin, United States)

Language:

English

Physical Description:

1 online resource

Place of Publication:

Warrendale, PA SAE International 2012

Summary:

During the last years the deep re-examination of the enginedesign for lowering engine emissions involved two-wheel vehiclestoo. The IC engine overall efficiency plays a fundamental role indetermining final raw emissions. From this point of view, theoptimization of the in-cylinder flow organization is mandatory. Indetail, in SI engines the generation of a coherent tumble vortexhaving dimensions comparable to the engine stroke could be ofprimary importance to extend the engines' ignition limitstoward the field of the dilute/lean mixtures.For motorbike and motor scooter applications, the optimizationof the tumble generation is considered an effective way to improvethe combustion system efficiency and to lower emissions,considering also that the two-wheels layout represents an obstaclein adopting the advanced post-treatment concepts designed forautomotive applications.The aim of the paper is to use the 3D-CFD simulation tool toassess the intake duct geometry influence on the tumble motiongeneration during both the intake and the compression strokes. Allthe CFD simulations presented in the paper were performed on a SI4-valve engine characterized by a unit displacement of 250 cm₃. Thetumble structure was changed during the analysis by changing theangle set defining the intake port shape. The stroke-to-bore engineratio was kept constant to 0.7. The effects of the tumblevariations were evaluated on the in-cylinder vortex characteristiclength and vorticity, and on the cylinder mean flow structure atIVC.3D-CFD simulations were performed by AVL-FIRE volume2010 CFDcode

Notes:

Vendor supplied data

Publisher Number:

2012-32-0095

Access Restriction:

Restricted for use by site license