Computational Fluid Dynamics (CFD) modeling was used to investigate the effects of the direct injection of wet ethanol at various injection timings during the intake stroke in a diesel engine with a shallow bowl piston. Thermally Stratified Compression Ignition (TSCI) has been proposed to expand the operating range of Low Temperature Combustion (LTC) by broadening the temperature distribution in the cylinder prior to ignition. TSCI is accomplished by injecting either water or a water-fuel mixture with a high latent heat of vaporization like wet ethanol. This current study focuses on isolating the effects that injecting such a high heat of vaporization mixture during the intake stroke has on the distribution of temperature and equivalence ratio in the cylinder before the onset of combustion. A CONVERGE 3-D CFD model of a single cylinder diesel research engine using Reynolds Averaged Naiver Stokes (RANS) turbulence modeling was developed and validated against experimental data. Then, five cases of injection timing with an injector included angle of 60° were simulated from -330 CAD to -210 CAD BTDC in increments of 30 CAD and five cases with an injector included angle of 150° were simulated from -330 CAD to -240 CAD BTDC also in increments of 30 CAD with an additional case at -340 CAD BTDC. For each spray case, the temperature and equivalence ratio stratification in the cylinder 10 CAD before TDC were analyzed using joint probability density functions (jPDFs). Results show that a later injection timing yields a more stratified mixture as well as a stronger inverse relationship between local temperature and equivalence ratio. An injection of wet ethanol at specific timings also causes the fuel to experience different mixing profiles due to the injector included angle and the piston position at each injection timing. Wall wetting on the piston was another area explored under varying spray conditions due to the high heat of vaporization of the fuel mixture.


    Access

    Check access

    Check availability in my library

    Order at Subito €


    Export, share and cite



    Title :

    Varying Intake Stroke Injection Timing of Wet Ethanol in LTC


    Additional title:

    Sae Technical Papers



    Conference:

    WCX SAE World Congress Experience ; 2020



    Publication date :

    2020-04-14




    Type of media :

    Conference paper


    Type of material :

    Print


    Language :

    English




    Combustion of Biodiesel- and Ethanol-Diesel Intake Injection Mixtures with

    Jones, B. C. / Gutteridge, C. E. / Leahey, D. M. et al. | SAE Technical Papers | 2007


    Variable intake valve timing

    Heinrich,H. / Adamis,P. / Volkswagen,Wolfsburg,DE | Automotive engineering | 1988


    Combustion of biodiesel-diesel and ethanol-diesel mixtures with intake injection

    Leahey,D.M. / Jones,B.C. / Gilligan,J.W. et al. | Automotive engineering | 2007


    Method of resuming multi-port injection using an intake stroke and a vehicle using same

    HAN MIN-KYU / HAN JUNG-SUK | European Patent Office | 2019

    Free access

    METHOD OF RESUMING MULTI-PORT INJECTION USING AN INTAKE STROKE AND A VEHICLE USING SAME

    HAN MIN-KYU / HAN JUNG-SUK | European Patent Office | 2018

    Free access