Numerical Assessment of an After-Treatment System equipped with a Burner to Speed-up the Light-off during Engine Cold Start Politecnico di Milano

Format:

Book

Conference/Event

Author/Creator:

Della Torre, Augusto, author.

Contributor:

Barillari, Loris

Montenegro, Gianluca

Onorati, Angelo

Paltrinieri, Stefano

Pulvirenti, Francesco

Rossi, Vincenzo

Rulli, Federico

Conference Name:

15th International Conference on Engines & Vehicles (2021-09-12 : Capri, Italy)

Language:

English

Physical Description:

1 online resource cm

Place of Publication:

Warrendale, PA SAE International 2021

Summary:

In the next years, the upcoming emission legislations are expected to introduce further restrictions on the admittable level of pollutants from vehicles measured on homologation cycles and real drive tests. In this context, the strict control of pollutant emissions at the cold start will become a crucial point to comply with the new regulation standards. This will necessarily require the implementation of novel strategies to speed-up the light-off of the reactions occurring in the after-treatment system, since the cold start conditions are the most critical one for cumulative emissions. Among the different possible technological solutions, this paper focuses on the application of a burner system, which is activated before the engine start. The burner exploits the lean combustion of an air-gasoline mixture to generate a high temperature gas stream which is directed to the catalyst section promoting a fast heating of the substrate. In this work, an experimental test bench has been adopted to characterize the thermal transient of the after-treatment system when the burner is activated, monitoring the temperature of the gas flow and the temperature of the metal walls in different locations. Moreover, a CFD model has been developed to investigate the light-off of the reactions during the initial operation of the burner and the subsequent start of the engine. The model, developed on the basis of the OpenFOAM code, resorts to a multi-region approach, where different meshes are employed to describe the fluid domain and the solid regions, namely catalytic porous substrates and metallic walls constituting pipes and canning. Specific models are implemented to consider flow resistance, heat transfer, mass transfer and catalytic reactions occurring in the catalyst regions. The CFD framework has been initially validated on the experimental data acquired on the test bench and then applied to evaluate different strategies for the operation of the burner

Notes:

Vendor supplied data

Publisher Number:

2021-24-0089

Access Restriction:

Restricted for use by site license