The use of Fischer-Tropsch (F-T) diesel synthesized from coal in automobiles can alleviate the shortage of petroleum and promote clean utilization of coal. In this study, the effects of injection timing (IT) and rail pressure (RP) on the brake thermal efficiency (BTE), combustion characteristics, and cyclic variations of F-T diesel were investigated on a turbocharged, 6-cylinder, common rail direct injection (CRDI) diesel engine. The results indicate that increasing RP results in higher BTE, whereas advancing IT results in an initial BTE increase and a subsequent BTE decrease. In comparison with petroleum diesel, the BTE of F-T diesel increased by 0.54% on average and by a maximum of 1% under different conditions. When the IT was advanced from 2 °CA to 18 °CA BTDC, the ignition delay periods (IDP) first decreased and then increased, whereas the combustion durations (CD) first lengthened and then shortened; peak cylinder pressure (PCP), peak pressure rise rate (PPRR), and peak combustion temperature (PCT) gradually increased; peak heat release rate (PHRR) first decreased and then increased at the low loads, whereas it always increased at medium and high loads. In comparison with petroleum diesel, the IDP of F-T diesel decreased by 22–31% at various conditions, and the CD was slightly longer than that of petroleum diesel at most conditions. Additionally, increasing RP resulted in a decrease in the IDP and CD, and a significant increase in PCP, PPRR, PHRR, and PCT. At low loads, the PPRR and PHRR of F-T diesel were 32.72% and 32.13% lower than that of diesel owing to the shorter ignition delay. This implies that using F-T diesel can help in attaining smoother engine running and has lower combustion noise. Advancing the injection timing or increasing the engine loads can decrease the cyclic variations, whereas increasing rail pressure results in the increment of COVp_max at low loads and the significant decrement of COVp_max at medium and high loads. In comparison with petroleum diesel, F-T diesel exhibits higher combustion stability owing to the better volatility and higher fuel reactivity.

在汽车中使用由煤合成的费托（FT）柴油可以减轻石油短缺，并促进煤炭的清洁利用。在这项研究中，研究了涡轮增压六缸共轨直喷时，喷射正时（IT）和导轨压力（RP）对制动热效率（BTE），燃烧特性和FT柴油循环变化的影响。 （CRDI）柴油发动机。结果表明，增加RP会导致更高的BTE，而提高IT会导致最初的BTE增加和随后的BTE减少。与石油柴油相比，FT柴油的BTE平均增加0.54％，在不同条件下最多增加1％。当IT从2°CA升高到18°CA BTDC时，点火延迟时间（IDP）先减小然后增加，燃烧时间（CD）先延长然后缩短；气缸峰值压力（PCP），峰值压力上升速率（PPRR）和峰值燃烧温度（PCT）逐渐增加; 在低负荷下，峰值放热率（PHRR）先降低然后增加，而在中负荷和高负荷下，峰值放热率总是增加。与石油柴油相比，FT柴油在各种情况下的IDP降低了22–31％，并且CD在大多数情况下比石油柴油的IDP略长。此外，RP的增加导致IDP和CD的减少，PCP，PPRR，PHRR和PCT的显着增加。在低负荷下，FT柴油的PPRR和PHRR分别比柴油低32.72％和32.13％，这是因为点火延迟更短。这意味着使用FT柴油可以帮助实现更平稳的发动机运行，并降低燃烧噪音。提前喷射正时或增加发动机负荷可以减少周期变化，而增加导轨压力会导致转速增加。COVP_最大值在低负荷和的显著递减COVP_最大，中等和高负荷。与石油柴油相比，FT柴油具有更高的挥发性和更高的燃料反应性，因此具有更高的燃烧稳定性。