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在柴油机领域中,日益严格的排放法规和用户的要求迫切需要先进的技术。柴油机的一个重要课题是在冷态条件下的冷起动能力和白烟排放。讨论在冷态条件下的多缸发动机的燃烧机理。首先,经证实,在起动条件下的断续燃烧期间由前面的未着火燃油所产生的冷火焰能促进在随后的循环中良好燃烧。第二,随着发动机的起动,确认存在着为进行燃烧所需的最小喷油量。该最小喷油量取决于燃烧室的温度。在最小喷油量和实际喷油量之间的不平衡就会产生白烟排放。根据这些分析,为了改善在冷态条件下的柴油机性能,使用了称为“ECD-U2”的共轨型喷油系统,采取了“复合喷油”的策略。确认能同时在冷起动能力和白烟排放方面获得很大的改善。
In the field of diesel engines, increasingly stringent emission regulations and user requirements urgently require advanced technology. An important issue for diesel engines is cold start capability and white smoke emission under cold conditions. Discusses the combustion mechanism of a multi-cylinder engine under cold conditions. First, it was confirmed that the cold flame produced by the preceding unburned fuel during intermittent combustion under starting conditions can promote good combustion in subsequent cycles. Second, as the engine starts, it is confirmed that there is a minimum amount of fuel required for combustion. The minimum amount of fuel injection depends on the temperature of the combustion chamber. White smoke emissions result from an imbalance between the minimum fuel injection and the actual fuel injection. Based on these analyzes, in order to improve diesel engine performance under cold conditions, a common rail fuel injection system called “ECD-U2” was adopted and a strategy of “compound fuel injection” was adopted. It has been confirmed that a great improvement can be achieved both in terms of cold start capability and white smoke emissions.