摘要
建立了一套基于激光诱导荧光法的光学试验装置 ,用高压共轨式电控喷射器喷射燃油 ,其喷射压力达 12 0MPa。此喷射器能在微机控制下实现预喷射和分段喷射。定容燃烧弹预先充上气体 ,其主要成分是氮气 ,还有一部分是乙炔和氧的混合气。在燃油喷射之前 ,点燃乙炔和氧的混合气 ,使燃烧室内的压力上升至 6 MPa,温度上升至10 0 0 K。试验结果与前期的气体射流模拟结果吻合 ,在燃烧室壁面设置限流沿后 ,所产生的二次射流可以形成稀薄的混合气区。因此 ,使用限流沿的新概念混合气形成过程有望用于降低柴油机的碳烟和 NOx
In this paper,a brief review is given on authors previous work of BUMP combustion.The effect of a BUMP chamber on the mixing process of an impinging fuel spray in diesel engine conditions was conducted due to means of gas jet simulation.It was found that the mixing rate of the secondary jet formed due to interaction of the impinging gas jet and a 1 mm BUMP was increased by more than 40 times than did without a BUMP. Based on the method of laser induced fluoresce (LIF),an optical experimental facility was set up.The diesel fuel was injected by a common rail high pressure injector.The maximum rail pressure is 120 MPa.The injector can realize pre injection and split injection,which is controlled by a PC based controller.The combustion vessel was fill ed with in high pressure nitrogen and a certain amount of C 2H 2+O 2 mixture,which sparked just before fuel injection and the pressure and temperature in the vessel were raised up to 6 MPa and above 1 000 K.The experimental results are qualitatively agreed well with the finding by gas jet simulation.A leaner and more even mixing zone was created due to the formation of the secondary jet by the BUMP on the chamber wall.Hopefully,the new concept of mixture formation by means of a BUMP could be applied to diesel engines to reduce soot and NO x emissions.
出处
《燃烧科学与技术》
EI
CAS
CSCD
2002年第4期338-341,共4页
Journal of Combustion Science and Technology
基金
中国自然科学基金资助项目 (599361 30 )
