Potential of Charge Stratification for Reducing Pressure-Rise Rate in HCCI Engines

HCCI 機関における燃焼時の圧力上昇率低減手法としての層状給気の効果

Charge Stratification has been thought as one of the ways to avoid the sharp pressure rises of HCCI combustion. The purpose of this study is to evaluate the potential of equivalence ratio, initial temperature, and EGR Stratifications to reduce Pressure Rise Rate on HCCI combustion. Pre-mixture with stratifications is charged into Rapid Compression Machine. After that, the pre-mixture is compressed and in that process, in-cylinder gas pressure and temperature are analyzed. Additionally numerical calculation with multi-zones model is run to know the potential of equivalence ratio, initial temperature, and EGR stratifications for reducing Pressure Rise Rate. This study investigates to expect the degree of stratification of in-cylinder charge shown in real engine from single-zone model. For clearly verifying the degree of stratification of in-cylinder charge, the results from single-zone model are compared with those from multi-zone model. The considered types of stratification of in-cylinder charge are thermal stratification, fuel stratification and EGR stratification. The comparison results between single-zone model and multi-zone model show that EGR stratification was most effective to disperse ignition timing compared to the thermal stratification and fuel stratification when setting the same time differences of ignition timing shown in single-zone model. Among the results from three type of stratification of in-cylinder charge, fuel stratification was the worst on disperse of ignition timing.HCCI機関の課題とされる高負荷時のノッキングを回避するために,給気予混合気に温度,当量比,EGR率等の分布を付与する,いわゆる層状給気が圧力上昇率を低減する効果について検討した.DMEと空気の予混合気を対象にマルチゾーンモデルによる素反応数値計算により検証した.

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  • English
  • Japanese

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  • Accession Number: 01673497
  • Record Type: Publication
  • Source Agency: Japan Science and Technology Agency (JST)
  • Files: TRIS, JSTAGE
  • Created Date: Jan 31 2018 3:22PM