Effect of Catalyst Inlet Cone Flow Mal-Distribution on Emissions Performance of a Close-Coupled Catalytic Converter Cambustion Limited

Format:

Conference/Event

Author/Creator:

Campbell, Bruce, author.

Conference Name:

SAE 2004 World Congress & Exhibition (2004-03-08 : Detroit, Michigan, United States)

Language:

English

Physical Description:

1 online resource

Place of Publication:

Warrendale, PA SAE International 2004

Summary:

The emissions performance of a prototype close-coupled catalyst system has been analysed and compared with semi-close-coupled and underfloor systems.Under certain engine conditions during the stabilized region of the ECE Stage 3 drive-cycle, the close-coupled system has showed higher emissions than the semi-close-coupled or underfloor configurations. Using fast response emissions analysers and catalyst warm-up characteristics in conjunction with Computational Fluid Dynamics (CFD), the reasons for this emissions performance deficit has been attributed to flow maldistribution across the front face of the catalyst.Two flow distribution-related mechanisms for emissions breakthrough have been isolated: radial variations in mean AFR (Air-Fuel Ratio) across the catalyst can cause localized emissions breakthrough due to cylinder-to-cylinder AFR variations; and under high space velocity conditions, localized breakthrough can occur due to radial variations in gas velocity through the catalyst

Notes:

Vendor supplied data

Publisher Number:

2004-01-1489

Access Restriction:

Restricted for use by site license