CAJ | 학술논문

本文中通过对奥迪EA8882.0L TFSI直喷汽油机进行台架试验,对比研究了压缩比改变前后发动机的离子电流与燃烧特性。结果表明：提高压缩比可使燃烧相位和离子电流相位提前；离子电流起始相位Ion10和离子电流差分谷值相位dIonval ey在反映燃烧相位时具有一致性,始终滞后于燃烧始点CA10和燃烧中心CA50一定的曲轴转角,约10oCA；压缩比从9.6提高到11.5,IMEP可上升约0.02MPa,相应指示热效率提高2%~3%；离子电流积分值Ionint与IMEP有很强的相关性,能够准确反映IMEP的变动；高压缩比使发动机爆燃倾向加剧,而离子电流振荡幅值fIonm 和差分峰值dIonpeak与爆燃强度有很强的正相关性。
본문중통과대오적EA8882.0L TFSI직분기유궤진행태가시험,대비연구료압축비개변전후발동궤적리자전류여연소특성。결과표명：제고압축비가사연소상위화리자전류상위제전；리자전류기시상위Ion10화리자전류차분곡치상위dIonval ey재반영연소상위시구유일치성,시종체후우연소시점CA10화연소중심CA50일정적곡축전각,약10oCA；압축비종9.6제고도11.5,IMEP가상승약0.02MPa,상응지시열효솔제고2%~3%；리자전류적분치Ionint여IMEP유흔강적상관성,능구준학반영IMEP적변동；고압축비사발동궤폭연경향가극,이리자전류진탕폭치fIonm 화차분봉치dIonpeak여폭연강도유흔강적정상관성。
Based on a bench test on EA888 2.0L TFSI direct injection gasoline engine, its ion current and combustion characteristics before and after the change of compression ratio ( CR) are comparatively studied. The re-sults show that increasing CR makes both combustion phase and ion current phase advance; the ion current initial phase Ion10 and the ion current difference valley dIonvalley have good consistency in reflecting combustion phase, and always lag around 10oCA behind compared with CA10 and CA50;The increase of CR from 9.6 to 11.5 brings about a 0.02MPa higher indicated mean effective pressure (IMEP), accordingly the indicated thermal efficiency in-creases by 2% ~3%;the ion current integral Ionint is strongly correlated to IMEP and can reflect the fluctuation of IMEP accurately;High CR exacerbate the tendency of engine knock and the ion current oscillation amplitude fIonm and the ion current difference peak dIonpeak have strong positive correlation with knock intensity.