A computer simulation for the performance of a four-stroke spark-ignition engine is used to assess the effects of in-cylinder flow processes on engine efficiency. The engine simulation model is a thermodynamic model coupled to submodels for the various physical processes of in-cylinder swirl, squish and turbulent velocities, heat transfer and flame propagation.The swirl and turbulence models are based on an integral formulation of the angular momentum equation and a K-ε turbulence model, These models account for the effects of changes in geometry of the intake system and the chamber design on in-cylinder flow processes. The combustion model is an entrainment burn-up model applicable to the mixing controlled region of turbulent flame propagation. The flame is assumed to propagate spherically from one or two spark plug locations. A heat transfer model that is dependent upon the turbulence level is used to compute the heat loss from the unburned and burned gases. These submodels are calibrated from experimental data.In this paper a combustion system featuring high and low swirl generating ports, a flat head and various piston designs is investigated. A parameter study is conducted to determine the effects of in-cylinder geometry on burn duration, heat transfer and fuel consumption. These results indicate that swirl, squish and turbulence intensity levels can be varied to produce a minimum in fuel consumption for the conditions examined. In addition, the isolated effect of the turbulence intensity on engine efficiency is presented for various EGR levels.


    Access

    Check access

    Check availability in my library

    Order at Subito €


    Export, share and cite



    Title :

    The Effect of In-Cylinder Flow Processes (Swirl, Squish and Turbulence Intensity) on Engine Efficiency — Model Predictions


    Additional title:

    Sae Technical Papers


    Contributors:

    Conference:

    SAE International Congress and Exposition ; 1982



    Publication date :

    1982-02-01




    Type of media :

    Conference paper


    Type of material :

    Print


    Language :

    English






    Effects of Swirl and Squish on S.I. Engine Combustion and Emission

    Nagayama, Isao / Iioka, Yasuo / Araki, Yasushi | SAE Technical Papers | 1977


    Squish-Swirl And Injection-Swirl Interaction In Direct-Injection Diesel Engines

    Miles, P.C. / RempelEwert, B.H. / Reitz, R.D. | British Library Conference Proceedings | 2003


    The Role of Swirl and Squish in Combustion of the Si Engine

    Inoue,T. / Nakanishi,K. / Noguchi,H. et al. | Automotive engineering | 1980