This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
Low Emission Engines for Heavy-Duty Natural Gas-Powered Urban Vehicles - Development Experience
Annotation ability available
Sector:
Language:
English
Abstract
The evolution and explanation of an approach to achieving a stated set of very low emissions limits was described in a previous paper (1)*. The method outlined was to use stoichiometric mixture preparation with EGR dilution in order to employ a 3-way catalyst for low emissions, whilst giving an engine power output competitive with a turbocharged diesel engine.
This approach has been followed in an engine development programme, which has resulted in a responsive and driveable engine being produced. The engine has demonstrated the achievability of very low emissions over the US heavy duty diesel transient test (FTP) cycle as follows:
The lean-burn approach to low emission heavy duty operation has also been considered, using steady-state engine test results. The NOx-HC trade-off has been identified as a key indicator of engines' potential, and is also considered to give an indication of the accuracy of air-fuel ratio control required to achieve proposed emissions standards.
Results from stoichiometric, naturally aspirated gas engines, indicate that they have potential for low emission operation using 3-way catalysts. Although considered unsuitable for heavy-duty application due to knock and temperature limitations, this type of engine could find use in light-medium duty applications, where greater torque and power then diesel engines and better efficiencies than gasoline engines would be attractive features.
Recommended Content
Authors
Topic
Citation
Hundleby, G. and Thomas, J., "Low Emission Engines for Heavy-Duty Natural Gas-Powered Urban Vehicles - Development Experience," SAE Technical Paper 902068, 1990, https://doi.org/10.4271/902068.Also In
References
- Hundleby G E “Low Emission Approaches for Heavy Duty Gas Powered Urban Vehicles” SAE 892134
- Mason J L Dr “Vehicular Fuel Economy and The Greenhouse Effect” 1990 IMechE/SAE Exchange Lecture
- Concawe 1989 Annual Report
- Heavenrich R M Murrell J D Hellman K H “Options for Controlling the Global Warming Impact from Motor Vehicles” EPA Technical Report EPA/AA/CTAB/89-08
- “Government Targets Cap on CO 2 Emissions by Year 2000” Manichi Daily News 19 June 1990
- Ekelund M “Low Emissions Conversion and Its Impact in the Market Place” NGV-88 Conference Sydney 27-30 October 1988
- Ekelund M “Development of NGV Markets in Sweden and Scandanavia as a Result of Scientific Engine Development” NGV-90 Conference Buenos Aires 21-24 October 1990
- Hundleby G E Ekelund M “The Development of an 11 Litre Scania Natural Gas Engine Operating with Very Low Emissions - A Co-Nordic Project Executed by Ricardo” NGV-90 Conference Buenos Aires 21-24 October 1990
- Kyriakides S C Glover A R “A Study of the Correlation Between in-Cylinder Air Motion and Combustion in Gasoline Engine” IMechE C55/88
- Tuttle J H Tagnel R R “Increased Burning Rates Offer Improved Fuel Economy-NOx Emissions Trade-Offs in Spark Ignition Engines” SAE 790388
- Kingston-Jones M G Heaton D M “Nebula Combustion System for Lean-burn, Spark Ignited Gas Engines” SAE 890211
- Dempster N M Shore P R “Analysis of Low Molecular Weight Hydrocarbons including 1,3 Butadiene, in Engine Exhaust using an Aluminium Oxide Porous Layer Open Tubular Fused Silica Column” Journal of Chromatographic Science May 1990
- Waldman D J Gladden J R Endicott D L Cull B A “Caterpillar 3406 Spark-Ignited Natural Gas Engine Emissions on EPA Heavy Duty Transient Test Cycle” GRI Topical Report GRI - 89/0085
- Lawson A Dr “Development of a Cummins L10 Natural Gas Bus Engine” NGV-88 Conference Sydney 27-30 October 1988
- Goetz W A Caning H de Voodg A “Closed Loop Fuel System and Low Emissions for a Natural Gas Engine” NGV-88 Conference Sydney 27-30 October 1988