柴油机燃用二元煤基燃料的燃烧和碳烟排放特性

Combustion and PM emission characteristics of dual coal fuel in diesel engine

为缓解石油短缺现状并降低柴油机有害物排放,采用二元煤基燃料在1115型单缸柴油机上进行了甲醇均质混合气F-T柴油引燃燃烧试验,对比分析了不同F-T柴油供油时刻和引燃量对燃烧和碳烟排放的影响。研究结果表明:随着供油时刻由16°CA BTDC提前至24°CA BTDC,碳烟排放最高降低27%,滞燃期变长,燃烧持续期先减小后增大,放热率中心先靠近后远离上止点;随着引燃量的增加,放热率中心缓慢接近上止点,滞燃期和燃烧持续期变短,中低负荷下,碳烟排放趋于平稳,高负荷下,碳烟排放逐渐变大。通过调整F-T柴油的供油时刻和引燃量可以对燃烧和碳烟排放进行匹配优化。

To ease the shortage situation of oil and reduce the emissions of diesel engine,the dual coal fuel experiment of F-T diesel pilot igniting methanol homogeneous charge was carried out on a 1115 type single cylinder diesel,and the combustion characteristics and PM emissions under various F-T diesel supply timing and ignition fuel were experimentally compared and analyzed.The results indicat- ed that with supply timing advancing from 16 ℃A BTDC to 24 ℃A BTDC,the highest emission of PM decreased by 27% ,ignition delay period increases and total combustion duration becomes shortening and then lengthening,and heat release rate curve center closes to and then leaves TDC gradually.With the ignition fuel increasing, heat release rate curve center closes to TDC slowly, both ignition delay pe- riod and total combustion duration continuously shorten,PM emission levels off under low and medium load and increases gradually under high load.Through the adjustment of F-T diesel supply timing and ignition fuel can match the optimization of combustion and PM emission.