机车柴油机燃油喷射系统新技术的研究

Research of the new technic in the field of diesel engine fuel injection system

针对机车柴油机燃油喷射系统的可靠性和油耗率、排放等方面开展了研究。通过理论计算、试验分析,对改进前后燃油系统的性能进行了分析和比较。柴油机试验和装车运用结果表明,采用90°密封座面的针阀偶件来降低升程,从而降低冲击应力,可以明显提高燃油喷射系统的可靠性。较小的喷孔孔径和较小的压力室容积等优化结构也有利于提高燃油喷射系统的可靠性和降低油耗率。进一步又对短针阀喷油器和低排放组合喷射技术开展了研究。经理论分析和计算发现,短针阀喷油器可以进一步降低针阀对密封座面的冲击应力。油雾颗粒分析试验表明,低排放组合喷射技术的油雾颗粒细化可以达到原喷油嘴的37%～65%,将对改善雾化起到积极作用。

We make scientific researches in to the diesel engine fuel injection system in terms of the reliability,the fuel consumption and the emission.The performances between non improved and improved fuel systems are analysed and compared based on theoretical calculations and test.The test and operation results show that using the needle valve set with a 90° sealed conical surface to decrease impact stress can obviously improve the reliability of fuel injection system.The optimization structure with a small diameter of injection apertures and a small sac volume is of benefit to improving reliability and decreasing specific fuel consumption.As the same time,we research on the short needle valve fuel injector and the low emission composite injection technique.By theoretical analysing and calculating,we find the short needle valve fuel injector can further decrease the impact stress of the needle valve to the sealed conical surface.The fuel spray partical analysing test shows that the fuel spray partical subdivision with the low emission composite injection technic can reach 37%～65% of the original.