Development of a two stroke direct injection jet ignition compressed natural gas engine

  • Alberto A. Boretti
  • Shuheng Jiang RMIT

Abstract

A traditional two stroke engine with crankcase scavenging also adopting exhaust red valve and lamellar intake is modified to accommodate a high pressure CNG direct injector and has the traditional spark plug replaced by a jet ignition device of same thread. The jet ignition device is a pre-chamber accommodating a gasoline GDI injector operated with CNG and an 8 mm racing spark plug. The jet ignition pre-chamber is connected to the main chamber through calibrated orifices. The CNG is injected after the exhaust post closes. The GDI injector operated with CNG introduces a slightly rich amount of fuel in the pre-chamber. The spark plug discharge initiates the pre-chamber combustion that then propagates to the main chamber though multiple jets of high energy partially burned hot combustion products that quickly ignite the main chamber mixtures. The CAD design of the engine including the jet ignition device is discussed in details. The CAE model of the engine is shown to produces efficiencies well in excess of 35% in the area of best operation. The load is controlled by finely tuning the injection and ignition events a reduced pollution and increasing the overall air-fuel ratio. The solution offer the opportunity to produce an efficient alternative to four stroke engines with improved power density running an alternative fuel having larger availability and better combustion properties and  reduced pollution than traditional diesel and gasoline fuels.  

References

[1] Yamaha (2013), Two Stroke HPDI. www.yamahaoutboards.com/outboards/2-Stroke-HPDI/overview
[2] Rotax (2013), E-TEC 800 R.
www.brp-powertrain.com/en/desktopdefault.
aspx/tabid-235/374_read-355/
[3] Rotax (2013), E-TEC 600 R.
www.brp-powertrain.com/en/desktopdefault.
aspx/tabid-232/371_read-349/
[4] Orbital (2013), Intellectual Property / FlexDI.
www.orbeng.com.au/intellectual-propertyflexdi.html
[5] TUM (2013), Investigation of a novel pre-chamber concept to improve ignition and combustion of lean premixed natural-gas-air mixtures in gas motors.
www.td.mw.tum.de/tum-td/en/de/forschung/themen/pgi_gasmotor
[6] CIMAC (2006), Recent Developments in 4 Stroke Engines.
www.cimac.com/cimac_cms/uploads/explorer/events_2006/6_Developments_in_4_Stroke_Diesel_Engines_Niven_Nerheim.pdf
[7] Boretti AA, Watson HC. Enhanced combustion by jet ignition in a turbocharged cryogenic port fuel injected hydrogen engine. Int J Hydrogen Energy. 2009;34(5):2511-6.
[8] Boretti AA, Watson HC. The lean burn direct injection jet ignition gas engine. Int J Hydrogen Energy. 2009;34(18):7835-41.
[9] Boretti AA. Stochastic reactor modelling of multi modes combustion with diesel direct injection or hydrogen jet ignition start of combustion. Int J Hydrogen Energy. 2012; 37(18):13555-63.
[10] Fleck, B., Fleck, R., Kee, R.J., Hu, X., Foley, L. and Yavuz, I., CFD Simulation and
Validation of the Scavenging Process in a 125cc 2-Stroke Racing Engine. SAE P.2006-32-0061. 2006.
[11] AVL (2013), BOOST - Advanced Engine Cycle, After treatment Fuel Injection and Duct Acoustic Simulation.
www.avl.com/boost1
[12] Ricardo (2013), WAVE.
www.ricardo.com/en-GB/What-we-do/Software/Products/WAVE/
Published
2014-06-06
How to Cite
BORETTI, Alberto A.; JIANG, Shuheng. Development of a two stroke direct injection jet ignition compressed natural gas engine. Journal of Power Technologies, [S.l.], v. 94, n. 3, p. 145--152, june 2014. ISSN 2083-4195. Available at: <https://papers.itc.pw.edu.pl/index.php/JPT/article/view/458>. Date accessed: 11 dec. 2024.
Section
Combustion and Fuel Processing

Keywords

2 stroke, direct injection, jet ignition

Most read articles by the same author(s)

Obs.: This plugin requires at least one statistics/report plugin to be enabled. If your statistics plugins provide more than one metric then please also select a main metric on the admin's site settings page and/or on the journal manager's settings pages.