基于调制多脉冲喷油模式的柴油预混合燃烧和排放特性的研究

Study of Characteristics of Premixed Diesel Combustion and Emissions Based on Modulated Multi-Pulse Injection Modes

在MULINBUMP-HCCI燃烧系统基础上,通过柔性调制多脉冲喷射的脉冲脉宽和间隔,形成了不同的喷油模式,以研究调制的多脉冲喷油模式对早喷HCCI燃烧和排放的影响。试验结果表明,改变多脉冲喷油模式,可以提高HCCI热效率,获得更高的输出功率,同时保持低的NOx和碳烟排放。5次和6次多脉冲喷射,递增式喷油方式具有很大的优势;对比不同次数的多脉冲喷射发现,增加多脉冲喷射次数可以扩大HCCI的负荷范围、提高指示热效率和降低CO排放。在110°CABTDC喷油定时,6次多脉冲喷射递增喷油方式6PIM相对于5次多脉冲喷射5PIM喷油方式的pIMEP和指示热效率分别提高了27.6%和13%,而CO排放减少了230%。

Based on the MULINBUMP-HCCI combustion system, the effects of the modulated multi-pulse injection modes on diesel-fueled HCCI combustion were investigated. By changing the controlling signals of pulse width and pulse dwell, a series of injection modes were realized according to the prejudgment of combustion requirement. The experimental results showed that HCCI combustion was sensitive to the injection mode, and the progressive increase mode gives higher thermal efficiency, higher power output and lower NO_x and Smoke emissions. At the injection timing of 110CA BTDC, p_(IMEP) and thermal efficiency of the 6PIM mode were 27.7% and 13% higher than those of 5PIM mode, while CO emission decreased by 230%.