Tests were carried out on a generator powered by a F186 diesel engine. A three-dimensional combustion model is established and validated by experimental data. The injection location and injection angle of each hole are considered in the model. Ten load cases were simulated. The results show that the maximum combustion pressure increases and the cylinder pressure also increases at the later combustion stage as the load increases, but the cylinder pressure decreases slightly with the increase of load during the compression stage. The initial ignition occurs in the region of initial spray peripheral near the underside of the nozzle, and the higher load results in the earlier combustion start point. The corresponding phase of the maximum combustion pressure is obviously advanced with the increase of load under light load, but the corresponding phase of the maximum combustion pressure is basically unchanged with further increase of load. The concentration gradient of NO distribution in the spatial region is basically the same at different loads. The NO concentration above the piston top surface is higher, and the injection angle of each nozzle has effect on the distribution of NO.%文章在一台以F186柴油机为动力的发电机上对乙醇掺混燃料进行试验,利用试验数据建立并验证三维燃烧模型的可靠性,该模型考虑了喷油器各喷孔的喷射位置与喷射角度,并针对10个负荷工况进行模拟.模拟结果表明:随着负荷的增大,最高燃烧压力逐渐增大,燃烧后期的气缸压力也随之增大,但在压缩阶段,随着负荷的增大,气缸压力略有减小;初始着火区域为初期喷雾外围靠近喷孔下侧的区域,负荷越大,燃烧始点越早;当负荷较小时,随着负荷的增大,最高燃烧压力对应的相位明显提前,而后随着负荷的进一步增大,最高燃烧压力对应的相位基本不变;负荷不同时,在空间区域上NO浓度分布的梯度变化基本相当,活塞顶面上方区域的NO浓度较高,喷孔喷射角度会对NO的分布产生影响.
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