This content is not included in your SAE MOBILUS subscription, or you are not logged in.
The Performance and Emissions of the Turbocharged Always Lean Burn Spark Ignition (TC-ALSI) Engine
ISSN: 0148-7191, e-ISSN: 2688-3627
Published April 12, 2010 by SAE International in United States
Annotation ability available
This paper extends previous development of the ALSI concept, by investigating the performance delivered with a turbocharged version of this engine.
The research is based on extensive experimental research with lean burn, high compression ratio engines using hydrogen, LPG, CNG and gasoline fuels. It also builds on recent experience with highly boosted spark ignition gasoline and LPG engines and single cylinder engine research used extensively for model calibration. The final experimental foundation is the wide ranging evaluation of jet assisted ignition that generally allows a lean limit mixture shift of more than one unit of lambda with consequential benefits of improved thermal efficiency and close to zero NOx.
The paper describes the capability of the ultra lean burn spark ignition engine with the mild boost needed provided by a Honeywell turbocharger. The concept is operation in the air-fuel ratio domain of the diesel engine but with essentially homogenous charge, although some stratification may be desirable. To achieve exceptional thermal efficiency this engine has optimised compression ratio but variable valve timing that enables reduction in the effective compression ratio under full load conditions. High specific power output is achieved by boosting the engine. To meet emission standards no NOx reduction is proposed with only an oxidation catalyst needed to meet Euro 6 standards.
The 2.6L four-cylinder engine is simulated using the group's well-developed PSO (particle swarm optimiser) engine simulation model that at a particular torque-speed, can rapidly find the local optimum engine configuration. It has been shown that the model accurately predicts the lean limit performance of both normal spark ignition and jet assisted ignition with LPG and other fuels.
Variable compression ratio is limited to 15 by mechanical constraints limit or to lower values because of knock or friction losses. Variable cam phasing is essential and results for variable inlet valve duration and fixed inlet valve duration cams are compared. In addition to power, thermal efficiency, and NOx emissions, operational characteristics of the engine are reported for optimum ignition timing, lambda, cam-phasing and boost/throttle.
The engine's maximum performance is a torque of 313 Nm and power of 147 kW with a fuel consumption reduction of around 50% over conventional SI at engine out NOx that meets Euro 6 standards.
CitationWatson, H. and Mehrani, P., "The Performance and Emissions of the Turbocharged Always Lean Burn Spark Ignition (TC-ALSI) Engine," SAE Technical Paper 2010-01-1235, 2010, https://doi.org/10.4271/2010-01-1235.
- Watson, H.C. Kumar, S. Kyaw, Z.H. Reduction of cyclic variability and lean limit operation of alternative fuels by pilot hydrogen in unmodified SI engines Proc. Eighth World Hydrogen Energy Conference Honolulu, Waikoloa 1990
- Kyaw, Z.H. Watson, H.C. “Hydrogen assisted jet ignition for near elimination of NOx and cyclic variability in the s.i. engine” Proceedings of the 24th International Symposium on Combustion Sydney 1 25 1992
- Lumsden, G. Watson, H.C. “Optimum Control of an S.I. Engine with a λ = 5 Capability,” SAE Technical Paper 950689 1995
- Glasson, N. Lumsden, G. Dingli, R. Watson, H. “Development of the HAJI System for a Multi-Cylinder Spark Ignition Engine,” SAE Technical Paper 961104 1996
- Lawrence, J. Hydrocarbon Emissions from a HAJI Equipped Ultra Lean Burn Engine University of Melbourne Parkville, Melbourne, Australia 1999
- Dober, G. Geometric Control of HC emissions The University of Melbourne Parkville, Melbourne, Australia 2002
- Karim, G.A. Watson, H.C. “Experimental and Computational Considerations of the Compression Ignition of Homogenous Fuel-Oxidant Mixtures,” SAE Technical Paper 710133 1971
- Watson, H.C. Milkins, E.E. Deslandes, J. The prediction and measurement of emissions, performance and efficiency of an homogeneous compression ignition engine Inst. Eng. Aust., Thermofluids Conf. Proc. 35 45 1974
- Karim G.A. Watson H.C. Experimental and Analytical Examination of the Development of Inhomogeneities and Autoignition During Rapid Compression of Hydrogen-Oxygen-Argon Mixtures ASME Journal of Gas Turbines and Power 123 225 237 2001
- Watson, H.C. Milkins, E.E. Goldsworthy, L.C. Optimising the spark ignition pre-chamber geometry including spark plug configuration for minimum NOx emissions and maximum efficiency Proc. XIX FISITA Congress SAE Australasia 13.1 13.7 1982
- Watson, H.C. Kumar, S. Kyaw, Z.H. Reduction of cyclic variability and lean limit operation of alternative fuels by pilot hydrogen in unmodified SI engines Proc. Eight World Hydrogen Energy Conference Honolulu, Waikoloa 1990
- Watson, H.C. Milkins, E.E. “Some Problems and Benefits from the Hydrogen Fuelled Spark Ignition Engine,” SAE Technical Paper 789212
- Gussak, L.A. “High Chemical Activity of Incomplete Combustion Products and a Method of Prechamber Torch Ignition for Avalanche Activation of Combustion in Internal Combustion Engines,” SAE Technical Paper 750890 1975
- Kyaw, Z.H. Watson, H.C. Hydrogen assisted jet ignition for near elimination of NOx and cyclic variability in the s.i. engine Proceedings of the 24th International Symposium on Combustion Sydney 1 25 1992
- Mehrani, P. Predicting knock in a HAJI engine University of Melbourne 2008
- Toulson, E. Watson, H.C. Attard, W.P. “The Effects of Hot and Cool EGR with Hydrogen Assisted Jet Ignition,” SAE Technical Paper 2007-01-3627 2007
- Toulson, E. Watson, H.C. Attard, W.P. “Modeling Alternative Prechamber Fuels in Jet Assisted Ignition of Gasoline and LPG,” SAE Technical Paper 2009-01-0721 2009
- Ratnaweera, A. Halgamuge, S.K. Watson, H.C. “Enhanced ICSI Engine Performance with Particle Swarm Optimization,” SAE Technical Paper 2004-28-0075 2004
- Ratnaweera, A. Halgamuge, S.K. Watson, H.C. “New SI Engine Optimization Techniques” FISITA Congress 2004 Technical Paper 2004V245 2004
- Mehrani, P. Watson, H.C. “Joint Efficiency and NOx Optimization Using a PSO Algorithm,” SAE Technical Paper 2006-01-1109
- Mehrani, P. Watson, H.C. “Modeling the Effects of Mixture Composition on Cyclic Variability,” SAE Technical Paper 2007-01-0672
- Mehrani, P. Watson, H.C. “Optimized Design of a Cyclic Variability Constrained Lean Limit SI Engine at Optimum NOx and Efficiency Using a PSO Algorithm,” SAE Technical Paper 2007-01-3551
- Watson, H. Khan, M.A. Liew, G. Baker, P. “Opportunities for Making LPG a Clean and Low Greenhouse Emission Fuel,” SAE Technical Paper 2005-01-2217
- Baker, P. Watson, H. “MPI Air/Fuel Mixing for Gaseous and Liquid LPG,” SAE Technical Paper 2005-01-0246 2005
- Khan, M.A. Watson, H. Baker P. Liew, G. et al. “SI Engine Lean-Limit Extension Through LPG Throttle-Body Injection for Low CO 2 and NO x ,” SAE Technical Paper 2006-01-0495
- Zakis G. Watson, H.C. “Lean Mixture Ignition Systems for CNG in Diesel Applications,” SAE Technical Paper 2004-28-0017
- Wang, D.E. Watson H.C. “Reducing HC emissions with Direct Injection of Natural Gas in a Hydrogen Assisted Jet Ignition Engine” IFP Conference Which Fuels For Low CO2 Engines? Paris June 2003
- Rosenkranz, H.G. Watson, H.C. Bryce, W. Lewis, A. “Driveability fuel consumption and emissions of 1.3 litre turbocharger spark ignition engine developed as a replacement for a 2 litre normally aspirated engine” Proc. I.Mech.E., C118/86:139-150 1986
- Attard, W. Watson, H.C. Konidaris, S. “Highly Turbocharging a Flow Restricted Two Cylinder Small Engine - Turbocharger Development,” SAE Technical Paper 2007-01-1562
- Hamori, F. “Optimising the Application of HAJI to the Supercharged Engine” University of Melbourne Australia 2004
- Watson, H.C. Mehrani, P. Brear, M.J. “The Always Lean Burn Spark Ignition (ALSI) Engine - Its Performance and Emissions,” SAE Technical Paper 2009-01-0932 2009
- Watson, H.C. Milkins, E.E. Preston, M.O. Chittleborough, C. et al. “Predicting Fuel Consumption and Emissions - Transferring Chassis Dynamometer Results to Real Driving Conditions,” SAE Technical Paper 830435 1983
- Watson, H.C. “Effects of a Wide Range of Drive Cycles on the Emissions from Vehicles of Three Levels of Technology,” SAE Technical Paper 950221 1995
- Das A. Watson H.C. “Development of a natural gas spark ignition engine for optimum performance” Proc. IMechE 211 D00496 1997
- Heywood, J.B. “Potential Impact of Alternative Powertrains on CO2 Emissions from the U.S. Light-Duty Vehicle Fleet. In Cost effective low carbon powertrains” IMechE 2006