A constant-volume combustion chamber was used to examine injection of a small quantity of slightly rich fuel/air mixture towards the spark plug around the time of ignition, in an overall very lean mixture rotating at velocities representative of modern spark-ignition engines. The results show that it is possible to achieve 100% ignitability with overall air-fuel ratios in excess of 50 and much faster burn rates than those with initially homogenous mixtures of the same equivalence ratio with high swirl and turbulence. The advantages of this method of local charge stratification have been demonstrated in terms of both pressure measurements and shadowgraphs of the early flame development while the transient characteristics of the injected rich mixture at the spark plug gap were monitored by a fast flame ionization detector. The implications of the proposed method for extending the lean limit of premixed fuel-air mixtures in spark-ignition engines are discussed and suggestions are made for its implementation in four-valve gasoline engines.


    Access

    Check access

    Check availability in my library

    Order at Subito €


    Export, share and cite



    Title :

    An Approach to Charge Stratification in Lean-Burn, Spark- Ignition Engines


    Additional title:

    Sae Technical Papers


    Contributors:

    Conference:

    International Fuels & Lubricants Meeting & Exposition ; 1994



    Publication date :

    1994-10-01




    Type of media :

    Conference paper


    Type of material :

    Print


    Language :

    English




    An Approach to Charge Stratification in Lean-Burn, Spark-Ignition Engines

    Arcoumanis, C. / Hull, D. R. / Whitelaw, J. H. et al. | British Library Conference Proceedings | 1994


    An Approach to Mixture Stratification in Lean-Burn Spark-Ignition Engines

    Hull, D. / Whitelaw, J. H. / Xu, H. M. et al. | British Library Conference Proceedings | 1995


    An approach to mixture stratification in lean-burn spark-ignition engines

    Hull,D. / Whitelaw,J.H. / Xu,H.M. et al. | Automotive engineering | 1995


    Optimizing local charge stratification in a lean-burn spark ignition engine

    Arcoumanis,C. / Hull,D.R. / Whitelaw,J.H. et al. | Automotive engineering | 1997