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Gasoline Engine Combustion — The Nebula Combustion Chamber
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Sector:
Event:
22nd FISITA Congress
Language:
English
Abstract
In view of the impending exhaust emission and fuel quality legislation in Europe, the motor industry is faced with developing engines giving low levels of HC and NOx emissions while operating on unleaded gasoline and retaining good fuel economy.
Ricardo have designed an advanced open chamber combustion system with vertical in-line valves, designated the “Nebula” combustion chamber. The design is based on converting the intake generated air motion into turbulence near to TDC, thus producing a fast burn characteristic. Initial development was carried out on a 86 × 86mm Hydra single cylinder research engine, where spark plug position and intake port swirl ratio were optimised. This work demonstrated potential of the “Nebula” concept which showed a considerable reduction in HC and NOx emissions at part load.
The “Nebula” combustion chamber has been applied to a 1.35 litre engine in a European vehicle. The engine is designed to use single point injection with microprocessor control of fuelling and ignition. The engine also utilises a simple variable geometry intake system which allows high swirl ratios to be used to give good lean mixture operation at light load, without degrading wide open throttle volumetric efficiency. Exhaust emissions and fuel economy potential are demonstrated over the ECE 15 drive cycle.
Authors
Citation
de Boer, C. and Grigg, D., "Gasoline Engine Combustion — The Nebula Combustion Chamber," SAE Technical Paper 885148, 1988, https://doi.org/10.4271/885148.Also In
References
- Hiring R.H. Overington M.T. “Gasoline Engine Combustion - The High Ratio Compact Chamber.” SAE 820166
- French C.C.J. A Universal Test Engine for Combustion Research SAE 830453
- Inoue T. Nakanishi K. Noguchi H. Iguchi S. “The Role of Swirl and Squish in Combustion of the S.I. Engine.” VDI 370 1980
- Gosman, A.D. Tsui Y.Y. Vafidis C. “Flow in a Model Engine with a Shrouded Valve - A Combined Experimental and Computational Study.” SAE 850498
- Kyriakides S.C. Glover A.R. “A study of the Correlation between In-Cylinder Air Motion and Combustion in Gasoline Engines.” Presented at IMECHE Conference May 1988
- Glover A.R. Hundleby G.E. Hadded O. “An Investigation into Turbulence in Engines using Scanning LDA.” SAE 880379
- European Patent Application No. 0150989AZ
- Analysis of Steady Flow Tests on Inlet and Exhaust Ports Ricardo DP 80/1123
- Overington M.T. de Boer C.D. “Vehicle Fuel Economy - High Compression Ratio and Supercharing Compared.” SAE 84242
- Clarke C.A. de Boer C.D. “Engine Control Stragtegy Development Using the Ricardo Microprocessor Engine Control Unit.” ISATA Cologne Sept. 83