Study of stratification of CNG mixture in a high charged SI engine

• Autorzy: Mitianiec W.
• Języki publikacji: EN

Abstrakty

EN

The burning of CNG mixture can occur in very small range of the compression pressure and lean mixture composition. The increased compression pressure requires a big pressure of CNG injection Even for lean mixtures the maximum combustion pressure reaches value near 200 bars. For very lean mixtures and higher compression ratios the misfire occurs, on the other hand for rich mixtures and high compression ratios the detonation is observed. For part load the fuel is injected during the compression stroke, which should form a bigger concentration of fuel near spark plug. The timing of injection should correlate with the piston position BTDC and engine speed in order to enable the adequate stoichiometric mixture near the spark plug during the ignition. The stratification of the charge depends on the location of the injector and the angles of injection nozzles and on the shape of the piston crown. The motion of the injected gaseous fuel required the adequate profile of piston head to turn the fuel stream directly to the spark plug. The flat piston causes that small part of fuel reaches the cylinder cavities and the increase of HC is observed. The paper performs results of calculations of the work engine parameters for 3 types of the piston shapes. The calculations were carried out in the 3-dimensional space with full engine geometry for the same engine speed and injection time. The simulations of CNG injection and combustion process were carried out for motorcycle engine SUZUKI DR-Z400S

Słowa kluczowe

EN

transport; SI four-stroke engine; fuelling

• Wydawca: Łukasiewicz Research Network - Institute of Aviation ; European Science Society of Powertrain and Transport KONES Poland ; Wydawnictwo Instytutu Technicznego Wojsk Lotniczych
• Czasopismo: Journal of KONES
• Rocznik: 2006
• Tom: Vol. 13, No. 2
• Strony: 323--333
• Opis fizyczny: Bibliogr. 7 poz., rys.

Twórcy

autor

Mitianiec W.

• Krakow University of Technology, Al. Jana Pawla II 37, 31-864 Krakow, Poland tel: [phone], fax: [phone],

Bibliografia

• [1] AGAWRAL A., ASSANIS D., Multi-Dimensional Modeling of Natural Gas Ignition Under Compression Ignition Conditions Using Detailed Chemistry, SAE Paper 980136
• [2] AMSDEN A.A., O'RURKE P.J., BUTLER T.D., KIVA-II – A Computer Program for Chemically Reactive Flows with Sprays, Los Alamos National Lab., LA-11560-MS, 1989
• [3] HEYWOOD J. B., Internal Combustion Engine Fundamentals, Mc Graw-Hill, 1988
• [4] MITIANIEC W., JAROSZEWSKI A..,Modele matematyczne procesów fizycznych w silnikach spalinowych małej mocy, Ossolineum, Wroclaw-Warszawa-Krakow, 1993
• [5] NAKANO D., SUZUKI T., MATSUI M., Gas Engine Ignition System for Long-Life Spark Plugs, SAE Paper 2004-32-0086 / 20044373, SETC Graz, 2004.
• [6] POLONI M., TAHIR A.,DANIZ M., Personal car engines powered by CNG, Journal of Kones, Vol. 10, No 1-2,Warsaw 2003.
• [7] ELHSNAWI M., TEODORCZYK A., Validation of detailed reaction mechanisms for simulations of combustion systems with gas injection, Journal of Kones, Vol. 9, No 1-2,Warsaw-Gdansk , 2002.