Design trend in spark ignition (SI) engines aims to improve power density and efficiency to ensure that regulated emissions levels are minimized. From a thermodynamic point of view this involves increased in-cylinder pressure and local mixture conditions that promote autoignition of the end gas, leading to knock. In order to prevent knock, the commonly used technique consists in retarding spark timing and combustion phasing, which results in a lower thermodynamic efficiency and higher exhaust temperature. A delayed spark timing is frequently coupled with over-fueling that allows to reduce the exhaust temperatures as well as knock tendency. This strategy clearly results in worsened fuel economy and increased emissions levels. At present time knock represents a limiting factor for a further development of new generation of high performance spark ignition engines and a number of technological solutions have been proposed by the scientific community and OEMs to overcome the limitations connected to this phenomenon. New engine architectures with optimized combustion chamber geometry shapes and combination of methodologies have been proposed for a reduced combustion time to enhance high-performance engines. Changes in the engine cooling systems have been applied to enhance end gas cooling leading to knock suppression effect. Other favorable options proposed for knock mitigation are water injection and cooled exhaust gas recirculation. Moreover, attention is also paid on renewable alcohol fuels with a research octane number higher than gasoline. This contribution aims to review some of the recent progresses in this topic with detailed analyses of current and promising future technologies to avoid knock and enable the development of future high efficiency SI powertrains with low impact on emissions.


    Zugriff

    Zugriff prüfen

    Verfügbarkeit in meiner Bibliothek prüfen

    Bestellung bei Subito €


    Exportieren, teilen und zitieren



    Titel :

    Technologies for Knock Mitigation in SI Engines—A Review


    Weitere Titelangaben:

    Energy, Environment, and Sustainability


    Beteiligte:
    Kalghatgi, Gautam (Herausgeber:in) / Agarwal, Avinash Kumar (Herausgeber:in) / Leach, Felix (Herausgeber:in) / Senecal, Kelly (Herausgeber:in) / Tornatore, Cinzia (Autor:in) / Marchitto, Luca (Autor:in) / Valentino, Gerardo (Autor:in)


    Erscheinungsdatum :

    2021-12-14


    Format / Umfang :

    25 pages





    Medientyp :

    Aufsatz/Kapitel (Buch)


    Format :

    Elektronische Ressource


    Sprache :

    Englisch




    Knock in Spark Ignition Engines

    By, A. / Kempinski, B. / Rife, J. M. | SAE Technical Papers | 1981


    Knock Behavior of SI-Engines: Thermodynamic Analysis of Knock Onset Locations and Knock Intensities

    Schubert, A. / Rothe, M. / Heidenreich, T. et al. | SAE Technical Papers | 2006


    Knock in Spark Ignition Engines

    By,A. / Kempinski,B. / Rife,J.M. et al. | Kraftfahrwesen | 1981


    Knock in spark ignition hydrogen engines

    Li, Hailin / Karim, Ghazi A. | Tema Archiv | 2004