This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
Optical Study of Swirl during Combustion in a CI Engine with Different Injection Pressures and Swirl Ratios Compared with Calculations
Technical Paper
2012-01-0682
ISSN: 0148-7191, e-ISSN: 2688-3627
Annotation ability available
Sector:
Language:
English
Abstract
Spray and mixture formation in a compression-ignition engine is
of paramount importance in the diesel combustion process. In an
engine transient, when the load increases rapidly, the combustion
system needs to handle low λ operation without producing high NOx
emissions and large amounts of particulate matter. By changing the
in-cylinder flow, the emissions and engine efficiency are affected.
Optical engine studies were therefore performed on a heavy-duty
engine geometry at different fuel injection pressures and inlet
airflow characteristics. By applying different inlet port designs
and valve seat masking, swirl and tumble were varied. In the engine
tests, swirl number was varied from 2.3 to 6.3 and the injection
pressure from 500 to 2500 bar. To measure the in-cylinder flow
around TDC, particle image velocimetry software was used to
evaluate combustion pictures. The pictures were taken in an optical
engine using a digital high-speed camera. Clouds of glowing soot
particles were captured by the camera and traced with particle
image velocimetry software. The velocity-vector field from the
pictures was thereby extracted and a mean swirl number was
calculated. The swirl number was then compared with 1D simulation
program GT-POWER and CFD-based correlations. The GT-POWER
simulations and CFD-based correlation calculations were initiated
from steady-state flow bench data on tested cylinder heads.
The main conclusions from this study were that the mean swirl
numbers, evaluated with the PIV software from combustion pictures
around TDC, agreed with CFD-based correlations and the low swirl
numbers also correlated with the 1D-simulation program. Most of the
induced swirl motion survives the compression and combustion, while
the induced tumble does not survive to the late combustion phase.
The tumble however, disturbs the swirl motion and offsets the swirl
center. This offset survives the compression and combustion. The
diesel sprays that are injected symmetrically in the combustion
chamber are thereby exposed to the swirl asymmetrically. This study
also shows that the angular velocity at different piston bowl radii
deviates from solid body rotation. The angular velocity is higher
closer to the center and decreases to be at the lowest value at the
outer piston bowl edge. When the injection pressure is increased,
the deviation from solid body rotation increases due to spray
effects.
Recommended Content
Authors
Topic
Citation
Dembinski, H. and Angstrom, H., "Optical Study of Swirl during Combustion in a CI Engine with Different Injection Pressures and Swirl Ratios Compared with Calculations," SAE Technical Paper 2012-01-0682, 2012, https://doi.org/10.4271/2012-01-0682.Also In
References
- Aronsson, U. Chartier, C. Andersson, Ö. Egnell, R. et al. “Analysis of the Correlation Between Engine-Out Particulates and Local Φ in the Lift-Off Region of a Heavy Duty Diesel Engine Using Raman Spectroscopy,” SAE Int. J. Fuels Lubr. 2 1 645 660 2009 10.4271/2009-01-1357
- Dembinski, H. Ångström, H. Dembinski, H. “An Experimental Study of the Influence of Variable In-Cylinder Flow, Caused by Active Valve Train, on Combustion and Emissions in a Diesel Engine at Low Lambda Operation,” SAE Technical Paper 2011-01-1830 2011 10.4271/2011-01-1830
- Suzuki, Takashi “The Romance of Engines.” 1997 1-56091-911-6
- Antila, E. Imperato, M. Kaario, O. Larmi, M. “Effect of Intake Channel Design to Cylinder Charge and Initial Swirl,” SAE Technical Paper 2010-01-0624 2010 10.4271/2010-01-0624
- Nordgren, H. Hildingsson, L. Johansson, B. Dahlén, L. et al. “Comparison Between In-Cylinder PIV Measurements, CFD Simulations and Steady-Flow Impulse Torque Swirl Meter Measurements,” SAE Technical Paper 2003-01-3147 2003 10.4271/2003-01-3147
- Deslandes, W. Dupont, A. Baby, X. Charnay, G. et al. “PIV Measurements of Internal Aerodynamic of Diesel Combustion Chamber,” SAE Technical Paper 2003-01-3083 2003 10.4271/2003-01-3083
- Deslandes, W. Dumont, P. Dupont, A. Baby, X. et al. “Airflow Cyclic Variations Analysis in Diesel Combustion Chamber by PIV Measurements,” SAE Technical Paper 2004-01-1410 2004 10.4271/2004-01-1410
- Petersen, B. Miles, P. “PIV Measurements in the Swirl-Plane of a Motored Light-Duty Diesel Engine,” SAE Int. J. Engines 4 1 1623 1641 2011 10.4271/2011-01-1285
- Auriemma, M. Caputo, G. Corcione, F. Valentino, G. “Influence of a Swirling Air Flow on an Evaporating Diesel Spray from a Common Rail Injection System under Realistic Engine Conditions,” SAE Technical Paper 2007-24-0021 2007 10.4271/2007-24-0021
- Lindström, M. Ångström, H. “A Study of In-Cylinder Fuel Spray Formation and its Influence on Exhaust Emissions Using an Optical Diesel Engine,” SAE Technical Paper 2010-01-1498 2010 10.4271/2010-01-1498
- Pires da Cruz, A. Baritaud, T. Poinsot, T. “Turbulent Self-Ignition and Combustion Modeling in Diesel Engines,” SAE Technical Paper 1999-01-1176 1999 10.4271/1999-01-1176
- Dembinski, Henrik Lewis, Clive “Miller-cycle on heavy duty diesel engines” Stockholm KTH 2009 Master Thesis
- Morel, T. Keribar, R. “A Model for Predicting Spatially and Time Resolved Convective Heat Transfer in Bowl-in-Piston Combustion Chambers,” SAE Technical Paper 850204 1985 10.4271/850204
- Morel, T. Rackmil, C. Keribar, R. Jennings, M. “Model for Heat Transfer and Combustion In Spark Ignited Engines and its Comparison with Experiments,” SAE Technical Paper 880198 1988 10.4271/880198
- Uzkan, T. Borgnakke, C. Morel, T. “Characterization of Flow Produced by a High-Swirl Inlet Port,” SAE Technical Paper 830266 1983 10.4271/830266
- Yu, R. Bai, X. Hildingsson, L. Hultqvist, A. et al. “Numerical and Experimental Investigation of Turbulent Flows in a Diesel Engine,” SAE Technical Paper 2006-01-3436 2006 10.4271/2006-01-3436
- Pastor, J. Margot, X. Gil, A. Donayre, J. “A Methodology to Estimate the Swirl Number at TDC In DI Diesel Engines: Through the Combination of CFD and Steady Flow Rig Results,” SAE Technical Paper 2004-01-1876 2004 10.4271/2004-01-1876
- Pope, Stephen B. “Turbulent flows” Cambridge University press 2000 978-0-521-59125-6