Abstract In this study, the performance of a diesel–ethylene glycol (DEG) dual-fuel engine with four low EG energy ratios (named EG0, EG5, EG10 and EG15 respectively) is tried to improve by port injection timing (PIT) and direct injection timing (DIT). The combustion results show that combustion process is even highly affected by DIT than by PIT. Peak cylinder pressure, peak heat release rates (PHRRs) and pressure rise rate increase with the augmentation of EG energy ratios and advanced DIT. Combustion duration decreases with the increase of EG energy ratios and advanced DIT. Brake thermal efficiency (BTE) can be improved 19.45% by raising EG energy ratios and advancing DIT. In consideration of emission, the emissions of NOx, THC, CO2 and soot decrease followed by the rise of EG energy ratio at the same time, while CO emission increases. The emission is more obviously affected by DIT than PIT. The emission of soot and THC decreases with advanced DIT, while the emission of CO2 and NOx increases. Advanced DIT can reduce PM, and EG can decrease the average diameter of PM. Overall, the advanced DIT, suitable EG energy ratio and proper PIT are expected to achieve optimization on DEG dual-fuel engine in the aspect of performance and emissions.

中文翻译：

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进气道喷射正时和直喷正时改进乙二醇/柴油双燃料发动机的燃烧和排放特性

摘要 在本研究中，试图通过进气道喷射正时（PIT）和直喷发动机改善具有四种低 EG 能量比（分别命名为 EG0、EG5、EG10 和 EG15）的柴油-乙二醇（DEG）双燃料发动机的性能。喷射正时（DIT）。燃烧结果表明，DIT 对燃烧过程的影响甚至高于 PIT。随着 EG 能量比和先进 DIT 的增加，峰值气缸压力、峰值热释放率 (PHRR) 和压力上升率增加。燃烧持续时间随着 EG 能量比和先进 DIT 的增加而减少。通过提高EG能量比和推进DIT，制动热效率（BTE）可提高19.45%。在排放方面，NOx、THC、CO2 和烟尘排放量减少，同时EG 能量比升高，而CO 排放量增加。排放受 DIT 的影响比 PIT 更明显。烟尘和 THC 的排放随着 DIT 的提高而减少，而 CO2 和 NOx 的排放增加。先进的DIT可以降低PM，EG可以降低PM的平均直径。总体而言，先进的DIT、合适的EG能量比和适当的PIT有望实现DEG双燃料发动机在性能和排放方面的优化。