Hydrogen Assisted Jet Ignition (HAJI) is a novel method of maintaining combustion stability during ultra-lean operation of conventional, homogeneously charged, SI engines. When operating with HAJI above λ=2, CO and NOx emissions fall to low levels while HC emissions rise to approximately double their stoichiometric value.HC emissions were investigated by operating a HAJI equipped, optically accessible, four-valve single cylinder engine at 600 r/min, wide open throttle (WOT), and from λ=1 to λ=2.4. A fast flame ionisation detector was used to collect real time hydrocarbon concentration data from behind one of the exhaust valves, inside the HAJI pre-chamber, and from near the combustion chamber wall. Flame images were also obtained.Exhaust port sampling shows that the HC concentration during blowdown and early exhaust is increased, but the concentration at the end of exhaust is decreased. Sampling from within the HAJI prechamber indicates that the prechamber is not acting as a HC storage mechanism, or ‘large crevice’. In-cylinder sampling near the wall shows that a thicker wall quench layer forms and is maintained throughout the cycle. This wall layer is markedly reduced in the region where the HAJI jet impinges on the wall. The structure and shape of the HAJI flame images support these findings.


    Access

    Check access

    Check availability in my library

    Order at Subito €


    Export, share and cite



    Title :

    Hydrocarbon Emissions from a HAJI Equipped Ultra-lean Burn SI Engine


    Additional title:

    Sae Technical Papers


    Contributors:

    Conference:

    International Congress & Exposition ; 1998



    Publication date :

    1998-02-23




    Type of media :

    Conference paper


    Type of material :

    Print


    Language :

    English




    Hydrocarbon emissions from a HAJI equipped ultra-lean burn SI engine

    Lawrence, J. / Watson, H.C. | Tema Archive | 1998


    Hydrocarbon Emissions from a HAJI equipped Ultra-lean Burn SI Engine

    Lawrence, J. / Watson, H. C. / Society of Automotive Engineers | British Library Conference Proceedings | 1998


    Hydrocarbon emissions from a HAJI equipped ultra-lean burn SI engine

    Lawrence,J. / Watson,H.C. / Univ.of Melbourne,US | Automotive engineering | 1998


    Hydrocarbon Emissions from a Gas Fueled SI Engine under Lean Burn Conditions

    Kim, Changup / Bae, Choongsik | SAE Technical Papers | 1999


    Hydrocarbon emissions from a gas fueled spark-ignition engine under lean burn conditions

    Kim,C. / Bae,C. / Korea Advanced Inst.of Science and Technol.,KR | Automotive engineering | 1999