This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
Effects of Injection Timing on the Conditions at Top Dead Center for Direct Injected HCCI
Technical Paper
2003-01-3219
ISSN: 0148-7191, e-ISSN: 2688-3627
Annotation ability available
Sector:
Language:
English
Abstract
A numerical approach has been applied to investigate direct injected HCCI combustion in terms of estimating the conditions at Top Dead Center (TDC) for three different injection timings during a calculated compression stroke in the commercial CFD software FIRE.
The paper first describes reproduction of the initial spray, which is introduced at different angles during the calculated compression stroke. These spray shapes have been validated by comparison to experimental investigations in a pressurized constant volume vessel with densities in accordance with the cylinder conditions. The sprays origins from a colliding flow nozzle, which is of interest in direct injected HCCI because of increased spray dispersion and turbulence.
In the calculated compression stroke two fuels were compared: n-dodecane and n-heptane. The injected amount of fuel, 117 mg, results in a generally lean distribution at TDC. For early injection the spray is distributed more homogenously with values close to the overall equivalence ratio, ϕgl=0.44, which is attractive for direct injected HCCI. When the fuel is injected later approaching TDC, a distribution with both lean and relatively rich fractions, ϕ>0.5, appears. These rich fractions are most likely to produce NOx.
Recommended Content
Topic
Citation
Strålin, P., Wåhlin, F., and Ångström, H., "Effects of Injection Timing on the Conditions at Top Dead Center for Direct Injected HCCI," SAE Technical Paper 2003-01-3219, 2003, https://doi.org/10.4271/2003-01-3219.Also In
References
- Nandha P Dependence of Fuel-Air Mixing Characteristics on Injection Timing in an Early-Injection Diesel Engine SAE paper 2002-01-0944 2002
- Sjöberg M Edling L-O Eliassen T Magnusson L Ångström H-E GDI HCCI: Effects of Injection Timing and Air Swirl on Fuel Stratification Combustion and Emissions Formation SAE paper 2002-01-0106 2002
- Dec J E Sjöberg M A Parametric Study of HCCI Combustion - the Sources of Emissions at Low Loads and the Effects of GDI Fuel Injection SAE Paper 2003-01-0752 2003
- Kong S-C Reitz R Christensen M Johansson B Modeling the Effects of Geometry Generated Turbulence on HCCI Engine Combustion SAE Paper 2003-01-(03P-138) 2003
- Akagawa H Miyamoto T Harada A Sasaki S Shimazaki S Hashizume T Tsujimura K Approaches to Solve Problems of the Premixed Lean Diesel combustion SAE Paper 1999-01-0183 1999
- Iwabuchi Y Kawai K Shoji T Takeda Y Trial of New Concept Diesel Combustion System - Premixed Compression-Ignited combustion SAE Paper 1999-01-0185 1999
- Yamamoto H Niimura K Characteristics of Fuel Sprays from Specially Shaped and Impinging Flow Nozzles SAE Paper 950082 1995
- Takeda Y Keiichi Na Keiichi Ni Emission Characteristics of Premixed Lean Diesel Combustion with Extremely Early Staged Fuel Injection SAE Paper 961163 1996
- Dukowicz J K A particle fluid numerical model for liquid sprays Journal of Comp Physics 35 1980
- FIRE Version 8, User Manual AVL GmbH 2002
- Dahlén L On Applied CFD and Model Development in Combustion Systems Development for DI Diesel Engines: Prediction of Soot Mediated Oil Thickening Doctoral thesis Department of Machine Design 13 2002
- O'Rourke Statistical properties and numerical implementation of a model for droplet dispersion in turbulent gas Journal of Comp Physics 83 1989
- Wåhlin F Impinging spray nozzle - A CFD study Master thesis Department of Machine Design 2001
- Liu A B Reitz R D Modelling the Effects of Drop Drag and Breakup on Fuel Sprays SAE 930072 1993
- von Kuensberg Sarre C et al. Modelling the Effects of Injector Nozzle Geometry on Dieselsprays SAE 1999-01-0912 1999