Abstract Based on a 4-cylinder turbocharged intercooler diesel engine fueled with n-butanol/diesel blends, this paper investigated the effect of various parameters on emissions under the early-injection partially premixed combustion (PPC) strategy and pre-injection PPC strategy. The potential for realizing PPC with different fuel reactivity and oxygen content was evaluated. The experimental results indicated that the peak value of heat release rate (HRR) increased and the heat release duration shortened after mixing the n-butanol under the same injection timing. The start of combustion (SOC) was advanced and the proportion of premixed combustion decreased as the growth of pre-injection ratio. The heat release process was delayed when the n-butanol ratio was increased. As the growth of n-butanol ratio, the peak value of the accumulation mode particles reduced and that of the nucleation mode particles increased sharply. The geometric mean diameter (GMD) of the particles was significantly reduced when the pre-injection timing was changed from −25 to −35° CA ATDC. As the growth of the pre-injection ratio, the GMD of the particulates had a tendency to decrease. Under the same pre-injection conditions, the total number and mass concentration of the particulates both reduced obviously with the increase of n-butanol ratio.

中文翻译：

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以高正丁醇-柴油比例混合为燃料的部分预混燃烧的颗粒排放特性研究

摘要 以正丁醇/柴油混合燃料4缸涡轮增压中冷柴油机为研究对象，研究了提前喷射部分预混燃烧（PPC）策略和预喷射PPC策略下各参数对排放的影响。评估了实现具有不同燃料反应性和氧含量的 PPC 的潜力。实验结果表明，在相同喷射时间下混合正丁醇后，放热率（HRR）峰值增加，放热持续时间缩短。随着预喷比的增大，燃烧开始时间提前，预混燃烧比例降低。当正丁醇比例增加时，放热过程被延迟。随着正丁醇比例的增长，积累模式粒子的峰值降低，成核模式粒子的峰值急剧增加。当预注射时间从 -25° CA ATDC 变为 -35° CA ATDC 时，颗粒的几何平均直径 (GMD) 显着降低。随着预喷射比的增加，颗粒物的 GMD 有降低的趋势。在相同的预注射条件下，随着正丁醇比的增加，颗粒总数和质量浓度均明显降低。