活化热氛围下润滑油自燃特性研究

Research on the Auto- ignition Characteristics of Lubricant in Controllable Active Thermo- Atmosphere

缸内直喷和增压已成为当今汽油机技术的主流方向,然而,随着发动机小型化和动力性的提高,增压汽油直喷发动机出现了一种新的异常燃烧现象——早燃,严重影响着发动机性能和使用寿命。文章主要研究活化热氛围下润滑油的着火延迟期,以探究润滑油成分对自燃特性的影响。在可控活化热氛围燃烧器台架的基础上进行了多组润滑油的实验,实验发现随着温度的升高,润滑油的着火延迟期显著降低。不同基础油、清净剂种类和钙含量都对润滑油的着火延迟期有明显影响。随着润滑油运动黏度的增加,着火延迟期增加;随着钙含量的增加,着火延迟期降低;蒸发损失对着火延迟期没有明显影响。

Turbocharging and direct injection are the main development trend of gasoline engine technologies. But with engine downsizing and power enhancement,an abnormal combustion phenomenon called pre- ignition emerges,which is the main obstacle to improve the power density and working life of the gasoline engine. This paper focuses on the ignition delay of different lubricants in Controllable Active Thermo- Atmosphere（ CATA） combustion system,to find out the influences of different lubricant components on the ignition characters. In this study,many tests were conducted in the CATA combustion system. The results of tests show that with the increase of the temperature,the ignition delay of the lubricant decreases obviously. The types of base oil and detergent and Calcium content of lubricant have evident impact; with the increase of the kinematic viscosity,the ignition delay increases. But with the increase of the Calcium content,the ignition delay decreases drastically. And the evaporation loss has almost no influence on the ignition delay of lubricant.