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The Effect of Injector and Intake Port Design on In-Cylinder Fuel Droplet Distribution, Airflow and Lean Burn Performance for a Honda VTEC-E Engine
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Abstract
The droplet velocity, size and distributions of iso-octane fuel from single hole and twin jet air-assist injectors have been measured by phase Doppler velocimetry in the pent-roof for two cylinder head designs of firing four-valve engines running at 1500 rpm, together with the airflow during induction and compression. The use of the twin jet air-assist injector together with the introduction of a transfer-passage between the two intake ports of a Honda VTEC-E valve train arrangement resulted in reduction in ISNOx and COV-1mep of the order of half of those with the single hole injector design without a transfer passage. Droplets, for both heads and injectors, having passed the inlet valves, impinged directly onto the sleeve opposite to their entry without striking the exhaust valves and had velocities up to 30 m/s and Sauter mean diameters which varied from 20 to 50pm. During the intake stroke, some air passed through the transfer-passage from the secondary intake valve VTEC-E port to the primary valve port and probably convected some evaporated fuel vapor thereby redistributing the proportion of fuel vapor entering the combustion chamber from each port relative to the design without the transfer passage. The use of the twin jet air-assist injector resulted in the impingement of droplets on the sleeve 15° CA earlier than for the single hole injector and to displacement of the location of maximum droplet flux by about 21/2 cm along the cylinder periphery, away from one exhaust valve and towards the primary inlet valve. In this region and over the duration of vapor release, approximately between 450° and 500° CA, the vapor cloud was convected by the air motion towards the cylinder head, in contrast to the use of the single hole injector which was generated at a location which resulted in convection of the corresponding cloud towards the piston crown. The pathlines during induction and compression of the rich vapor clouds are therefore different, providing evidence of a different mechanism for mixture stratification for the engine with the twin jet air-assist injector accounting for the improvement in ISNOx and COV-imep observed in the dynamometer tests.
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Carabateas, N., Taylor, A., Whitelaw, J., Ishii, K. et al., "The Effect of Injector and Intake Port Design on In-Cylinder Fuel Droplet Distribution, Airflow and Lean Burn Performance for a Honda VTEC-E Engine," SAE Technical Paper 961923, 1996, https://doi.org/10.4271/961923.Also In
References
- Quader A.A. “The Axially-Stratified-Charge Engine” SAE Paper 820131 1982
- Brown C.N. Ladomatos N. “A Numerical Study of Fuel Evaporation and Transportation in the Intake Manifold of a Port-Injected Spark-Injection Engine” Proc Inst Mech Engrs 285 161 175 1991
- Kadota T. Mizutani S. Wu C.Y. Hoshino M. “Fuel Droplet Size Measurements in the Combustion Chamber of a Motored S.I. Engine via Lase Mie Scattering” SAE Paper 900477 1990
- Inoue T. Matsushita S. Nakanishi K. Okano H. “Toyota Lean Combustion System: The Third Generation System” SAE 93087 1993
- Kiyota Y. Akishino K. Ando Hiromitsu “Concept of Lean Combustion by Barrel Stratification” SAE Paper 920678 1992
- Horie K. Nishizawa K. Ogawa T. Akazaki S. Miura K. “The Development of a High Fuel Economy and High Performance Four-Valve Lean Burn Engine” SAE Paper 920455 1992
- Quissek F. Bandel W. Mikulic L.A. “The AVL High Compression Lean Burn-Engine Development and Passenger Car Application” SAE Paper 880575 1988
- Stokes J. Lake T.H. Christie J. Denbratt I. “Improving the NOx/Fuel Economy Trade-Off for Gasoline Engines with the CCVS Combustion System” SAE Paper 940482 1994
- Hardalupas Y. Taylor A.M A.M.K.P. Whitelaw J.H. Ishii K. Miyano H. Urata Y. “Influence of Injection Timing on In-Cylinder Fuel Distribution in a Honda VTEC-E Engine” SAE Paper 950507 1995
- Berckmueller M. Tait N.P. Lockett R.D. Greenhalgh D.A. “In-Cylinder Crank Angle Resolved Imaging of Fuel Concentration in a Firing Spark-Ignition-Engine Using Planar LIFS” Twenty-fifth Symposium (international) on Combustion Irvine CA 1994
- Urata Y. Yoshida K. Ohono T. Ishii K. “Three Component Particle Velocimetry Using Laser Sheets for Cycle-Resolved, In-Cylinder Measurement” Honda Technical Review August 1996
- Carabateas N.E. Taylor A.M.K.P. Whitelaw J.H. Ishii K. Miyano “Droplet Velocities within the Pent-Roof of a Honda VTEC Cylinder Head” Paper 218 of the Second International Conference on multiphase flow Kyoto, Japan 1995
- Hardalupas Y. Okamoto S. Taylor A.M.K.P. Whitelaw J.H. “Application of a Phase Doppler Anemometer to a Spray Impinging on a Disc” Laser Techniques and Applications in Fluid Mechanics 490 506 Springer-Verlag Berlin 1992