[article]
Titre : |
Effects of the re-entrant bowl geometry on a DI turbocharged diesel engine performance and emissions : a CFD approach |
Type de document : |
texte imprimé |
Auteurs : |
S. Pasupathy Venkateswaran, Auteur ; G. Nagarajan, Auteur |
Année de publication : |
2011 |
Article en page(s) : |
10 p. |
Note générale : |
Génie Mécanique |
Langues : |
Anglais (eng) |
Mots-clés : |
Combustion Computational fluid dynamics Diesel engines Diffusion Fuel systems Shapes (structures) Turbulence |
Index. décimale : |
620.1 Essais des matériaux. Défauts des matériaux. Protection des matériaux |
Résumé : |
The purpose of this study is to investigate the influence of re-entrant bowl geometry on both engine performance and combustion efficiency in a direct injection (DI), turbocharged diesel engine for heavy-duty applications. The piston bowl design is one of the most important factors that affect the air–fuel mixing and the subsequent combustion and pollutant formation processes in a DI diesel engine. The bowl geometry and dimensions, such as the pip region, bowl lip area, and toroidal radius, are all known to have an effect on the in-cylinder mixing and combustion processes. Based on the idea of enhancing diffusion combustion at the later stage of the combustion period, three different bowl geometries, namely, bowl 1 (baseline), bowl 2, and bowl 3 were selected and investigated. All the other relevant parameters, namely, compression ratio, maximum diameter of the bowl, squish clearance and injection rate were kept constant. A commercial CFD code STAR-CD was used to model the in-cylinder flows and combustion process, and experimental results of the baseline bowl were used to validate the numerical model. The simulation results show that, bowl 3 enhance the turbulence and hence results in better air-fuel mixing among all three bowls in a DI diesel engine. As a result, the indicated specific fuel consumption and soot emission reduced although the NOx emission is increased owing to better mixing and a faster combustion process. Globally, since the reduction in soot is larger (−46% as regards baseline) than the increase in NOx (+15% as regards baseline), it can be concluded that bowl 3 is the best trade-off between performance and emissions. |
DEWEY : |
620.1 |
ISSN : |
0742-4795 |
En ligne : |
http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JETPEZ00013 [...] |
in Transactions of the ASME . Journal of engineering for gas turbines and power > Vol. 132 N° 12 (Décembre 2010) . - 10 p.
[article] Effects of the re-entrant bowl geometry on a DI turbocharged diesel engine performance and emissions : a CFD approach [texte imprimé] / S. Pasupathy Venkateswaran, Auteur ; G. Nagarajan, Auteur . - 2011 . - 10 p. Génie Mécanique Langues : Anglais ( eng) in Transactions of the ASME . Journal of engineering for gas turbines and power > Vol. 132 N° 12 (Décembre 2010) . - 10 p.
Mots-clés : |
Combustion Computational fluid dynamics Diesel engines Diffusion Fuel systems Shapes (structures) Turbulence |
Index. décimale : |
620.1 Essais des matériaux. Défauts des matériaux. Protection des matériaux |
Résumé : |
The purpose of this study is to investigate the influence of re-entrant bowl geometry on both engine performance and combustion efficiency in a direct injection (DI), turbocharged diesel engine for heavy-duty applications. The piston bowl design is one of the most important factors that affect the air–fuel mixing and the subsequent combustion and pollutant formation processes in a DI diesel engine. The bowl geometry and dimensions, such as the pip region, bowl lip area, and toroidal radius, are all known to have an effect on the in-cylinder mixing and combustion processes. Based on the idea of enhancing diffusion combustion at the later stage of the combustion period, three different bowl geometries, namely, bowl 1 (baseline), bowl 2, and bowl 3 were selected and investigated. All the other relevant parameters, namely, compression ratio, maximum diameter of the bowl, squish clearance and injection rate were kept constant. A commercial CFD code STAR-CD was used to model the in-cylinder flows and combustion process, and experimental results of the baseline bowl were used to validate the numerical model. The simulation results show that, bowl 3 enhance the turbulence and hence results in better air-fuel mixing among all three bowls in a DI diesel engine. As a result, the indicated specific fuel consumption and soot emission reduced although the NOx emission is increased owing to better mixing and a faster combustion process. Globally, since the reduction in soot is larger (−46% as regards baseline) than the increase in NOx (+15% as regards baseline), it can be concluded that bowl 3 is the best trade-off between performance and emissions. |
DEWEY : |
620.1 |
ISSN : |
0742-4795 |
En ligne : |
http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JETPEZ00013 [...] |
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