This content is not included in your SAE MOBILUS subscription, or you are not logged in.
A Comparison of the Flow Fields Generated for Spark and Controlled Auto-ignition
ISSN: 0148-7191, e-ISSN: 2688-3627
Published May 19, 2003 by SAE International in United States
Annotation ability available
Valve timing strategies aimed at producing internal exhaust gas re-circulation in a conventional spark ignition, SI, engine have recently demonstrated the ability to initiate controlled auto-ignition, CAI. Essentially the exhaust valves close early, to trap a quantity of hot exhaust gases in-cylinder, and the fresh air-fuel charge is induced late into the cylinder and then mixing takes place. As a logical first step to understanding the fluid mechanics, the effects of the standard and modified valve timings on the in-cylinder flow fields under motored conditions were investigated. Laser Doppler anemometry has been applied to an optical engine that replicates the engine geometry and different valve cam timings. The cycle averaged time history mean and RMS velocity profiles for the axial and radial velocity components in three axial planes were measured throughout the inlet and compression stroke. The turbulent mixing for the two cases are described in terms of the flow field maps of the velocity vectors, vorticity and turbulence kinetic energy and the integrated tumble ratio as a function of crankangle.
|Technical Paper||Influence of Inlet Flows on the Flow Field in an Engine|
|Technical Paper||Turbulence Length Scale Measurements by Two-Point Laser Doppler Anemometry in a Steady Flow|
|Technical Paper||A Study on the Flow in the Engine Intake System|
CitationPitcher, G., Turner, J., Wigley, G., and Chen, R., "A Comparison of the Flow Fields Generated for Spark and Controlled Auto-ignition," SAE Technical Paper 2003-01-1798, 2003, https://doi.org/10.4271/2003-01-1798.
- Lavy at al Innovative Ultra Low NOx Controlled Auto Ignition Combustion Process for Gasoline Engines SAE 2000-01-1837
- Law D. Allen J. Kemp D. Williams P. 4-Stroke Active Combustion (Controlled Auto-Ignition) Investigations Using a Single Cylinder Engine with Lotus Active Valve Train (AVT) 21 st Century Emissions Technologies Conference Inst.Mech.Eng. London 4-6th December 2000
- Law D. Kemp D. Allen J. Kirkpatrick G. Copland T. Controlled Combustion in an IC Engine with Fully Variable Valve Train SAE 2001-01-0251
- Allen J. Law D. Advanced Combustion Using a Lotus Active Valve Train; Internal Exhaust Gas Recirculation Promoted Auto-Ignition Proc. IFP International Congress, A New Generation of Engine Combustion Processes for the Future? IFP Paris 26-27th November 2001
- Ando H. Kuwahara K. A Keynote on Future Combustion Engines SAE 2001-01-0248
- Wigley G. Hargrave G.K. Heath J. A High Power, High Resolution LDA/PDA System Applied to Dense Gasoline Direct Injection Sprays ILASS-Europe Lisbon 1998
- Jackson N.S. Stokes J. Sadler M. Heikal M.R. Faura M. Pommler L. Correlation of the Combustion Characteristics of Spark Ignition Engines With In-Cylinder Flow Field Analysis Using PIV in a Water Analogy Rig SAE 971637
- Pitcher G. Wigley G. LDA Analysis of the Tumble Flow Generated in a Motored 4 Valve Engine 9 th Int.Conf., Laser Anemometry Advances and Applications Limerick September 2001