Experimental and numerical analysis on the influences of direct fuel injection into oxygen-depleted environment of a homogeneous charge compression ignition engine

Ratnak Sok, Kei Yoshimura, Kenjiro Nakama, Jin Kusaka

研究成果: Article査読

抄録

The oxygen-depleted environment in the recompression stroke can convert gasoline fuel into light hydrocarbons due to thermal cracking, partial oxidation, and water-gas shift reactions. These reformate species can influence the combustion characteristics of gasoline direct injection homogeneous charge compression ignition (GDI-HCCI) engines. In this work, the combustion phenomena are investigated using a single-cylinder research engine under a medium load. The main combustion phases are experimentally advanced by direct fuel injection into the negative valve overlap (NVO) compared with that of intake stroke under single/double-pulse injections. NVO peak in-cylinder pressures are lower than that of motoring due to the limited O2 concentration, emphasizing that endothermic reactions occur during the overlap. This phenomenon limits the oxidation reactions, and the thermal effect is not pronounced. The zero-dimensional chemical kinetics results present the same increasing tendencies of classical reformed species of rich mixture such as C3H6, C2H4, CH4, CO, and H2 as functions of injection timings. Predicted ignition delays are shortened due to the additions of these reformed species. The influences of the reformates on the main combustion are confirmed by three-dimensional computational fluid dynamics (CFD) calculations, and the results show that OH radicals are advanced under NVO injections relative to intake stroke injections. Consequently, earlier heat release and cylinder pressure are noticeable. Parametric studies on the effects of injection pressure, double-pulse injection, and equivalence ratio on the combustion and emissions are also discussed experimentally.

本文言語English
論文番号122302
ジャーナルJournal of Energy Resources Technology, Transactions of the ASME
143
12
DOI
出版ステータスPublished - 2021 12

ASJC Scopus subject areas

  • 再生可能エネルギー、持続可能性、環境
  • 燃料技術
  • エネルギー工学および電力技術
  • 機械工学
  • 地球化学および岩石学

フィンガープリント

「Experimental and numerical analysis on the influences of direct fuel injection into oxygen-depleted environment of a homogeneous charge compression ignition engine」の研究トピックを掘り下げます。これらがまとまってユニークなフィンガープリントを構成します。

引用スタイル