In the context of the global response to climate change, methanol is receiving widespread attention as a potentially clean, renewable fuel. In this paper, the effects of injection timing and split injection strategy on the combustion process and emissions were investigated in methanol engines. The effect of mixture control on the ignition delay period was studied in detail. The results showed that when the injection timing was advanced to 95 °CA bTDC, the ignition delay period and combustion duration period were reduced by 28.96 % and 6.14 %, respectively. When the injection timing was delayed, the NO emissions of the methanol engine were significantly reduced by 6.13 %–20.39 %. The use of split injection strategy enables the formation of a reasonably stratified fuel-air mixture in the cylinder. Under the optimized split injection strategy, the combustion duration was shortened by 0.93 %–14.58 %. The ignition delay period of the IT105S2 was shortened by 28.62 % compared with that of the original engine. In addition, the reasonable split injection strategy can effectively reduce the emission of formaldehyde and unburned methanol. This study provides an optimization direction for the application of methanol in the internal combustion engine for high efficiency and clean combustion.

中文翻译：

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喷射策略对缸内燃烧过程及甲醇排放的影响研究


在全球应对气候变化的背景下，甲醇作为一种潜在的清洁、可再生燃料受到广泛关注。本文研究了甲醇发动机的喷射正时和分次喷射策略对燃烧过程和排放的影响。详细研究了混合气控制对点火延迟期的影响。结果表明，当喷油正时提前至95°CA bTDC时，点火延迟期和燃烧持续期分别缩短了28.96%和6.14%。延迟喷射正时时，甲醇发动机的NO排放量显着降低了6.13%~20.39%。采用分流喷射策略可以在气缸内形成合理分层的燃油-空气混合物。在优化的分流喷射策略下，燃烧持续时间缩短了0.93%~14.58%。 IT105S2的点火延迟期比原发动机缩短了28.62%。此外，合理的分流喷射策略可以有效减少甲醛和未燃甲醇的排放。该研究为甲醇在内燃机中的应用实现高效清洁燃烧提供了优化方向。