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Air -Fuel Ratio Calculation for a Natural Gas Fuelled Spark Ignition Engine
ISSN: 0148-7191, e-ISSN: 2688-3627
Published March 08, 2004 by SAE International in United States
Annotation ability available
Air-fuel ratio (AFR) is a crucial parameter for combustion controls in internal combustion engines. An incorrect AFR metering for reciprocating internal combustion engine causes high toxic gases emissions formulation, serious fuel consumption problems and unbearable combustion noise and combustion deterioration. Traditionally, the AFR is obtained by direct measurement of intake air and the fuel either injected into the combustion chamber or pre-mixed at the carburetor. However, the accurate AFR obtained from direct measurement is difficult due to measuring equipments resolution prone to errors.
This paper describes a method for accurate determination of air-fuel ratio based on exhaust emission gas analysis as an additional tool used to be validated the conventional direct air fuel flow rates measurement. This method explains all the possible parameters that may affect the accuracy of air-fuel ratio measurement which includes the instrument error, ambient conditions, the assumed water-gas shift reaction constant, the humidity of the atmospheric air and the inclusion of nitrogen in the air-fuel ratio model.
Results show that four essential exhaust gas emission concentrations, namely carbon monoxide (CO), carbon dioxide (CO2), oxygen (O2) and unburn hydrocarbons (HCs) are adequate for obtaining an accurate air-fuel ratio. The fuel type and the range of parameters that may affect the accuracy of air-fuel ratio are properly defined. This paper will also present experimental results of a bi-fuel natural gas spark ignition engine to be compared with computational results. The results of this investigation will be used to develop a new dedicated natural gas engine.
CitationKalam, M., Masjuki, H., Maleque, M., Amalina, M. et al., "Air -Fuel Ratio Calculation for a Natural Gas Fuelled Spark Ignition Engine," SAE Technical Paper 2004-01-0640, 2004, https://doi.org/10.4271/2004-01-0640.
- Yoshida, Y. Oguchi, M. Gen, S. “Measuring Method of Fuel Consumption for Natural Gas Vehicles,” SAE paper 2003-01-2009 2003
- Keshav, S.V. “Combustion Variability in Natural Gas Fuelled Engines,” SAE Paper 2003-01-1935 2003
- “Vehicle Registration in Malaysia” Department of Road Transport Malaysia January 31 2003 Source: Ministry of Transport, Malaysia
- Faridon, B.I. Azman, B.M. Abdullah, M.A. “NGV: Petronas Research Experience,” Petronas Research and Scientific Co. Ltd. 1 30 2000 Malaysia
- Fagley, W.S. Nunez, R.R. “Exhaust Gas Analysis as a Tool for Measuring Air/Fuel Ratios,” SAE Paper 670483 1967
- Chan, S.H. “An Exhaust Emissions Based Air-Fuel Ratio Calculation For Internal Combustion Engines, Journal Of Automobile Engineering,” I.Mech.E. Part D. 1993 273 280
- Eltinge, L. “Fuel/Air Ratio And Distribution From Exhaust Gas Composition.” SAE Paper 680114 1968
- Heywood Jhon B. “Internal Combustion Engine Fundamentals,” Mcgraw-HILL International Editions 140 160
- Shii, H.S. Masjuki, H.H. Abdulmuin, M.Z. “Auto Ignition of Natural Gas Fuelled Engines,” A Review of Its Possibilities, Journal of Mechanical Engineering Research and Development 17 1994 1 11
- Kalam, M.A. Masjuki, H.H. Maleque, M.A. 2001 “Gasoline Engine Operated on Compressed Natural Gas,” Proceed. of Advances in Malaysian Energy Research (Amer) 2001 4 - 5 October 307 316
- Boam, J.D. 1993 “Modal Assessment of Hydrocarbons Reduction Technologies in Vehicle During Engine Warm-up,” Proc. of IMechE London 1993 177 187
- Hotchmuch, K.J. Burk, L.P. Tolentino, M.C. Michael, J. “Hydrocarbon Traps for Controlling Cold Start Emissions,” SAE 930739 , Journal of Fuels and Lubricants, SAE, Section 4 102 607 620
- Byung, H.M. Chung, J.T. Kim, H.Y. Simsoo, P. “Effects of Gas Composition on the Performance and Emissions of Compressed Natural Gas Engines,” KSME International Journal Korea 16 2 2002 219 226
- Hamzah, A.H. Ahmad, A.S. 2002 “Development of Monofuelled Natural Gas Vehicles, a Malaysian Experience,” Special Project of Petronas Research Co. Ltd. Malaysia 1 48
- Ali Sera Mardani Abu Bakar Rosli Kwan Leong Sin “CNG Engine Performance Improvement Strategy Through Advanced Intake System,” SAE paper 2003-0101937 2003
- Masjuki, H.H. Kalam, M. A. Maleque, M.A. Kubo A Nonaka T “Performance, Emissions and Wear Characteristics of an Indirect Injection Diesel Engine Using Coconut Oil Blended Fuel,” ‘Journal of Automobile Engineering (Part D), I.Mech.E’ London 2001 215 3 393 404
- Xinghu Li. Xiaofeng Z. “The Properties of Gasoline And Effect Of This Properties In Calculation Of Air-Fuel Ratio,” SAE Paper 2003-01-1911 2003