Experimental study on evaporation characteristics of lubricating oil/gasoline blended droplet

The auto-ignition of lubricating oil/gasoline blended droplet is one of super-knock origins in gasoline direct injection engine. This paper investigates the effect of ambient temperature and blended ratio on evaporation characteristics of lubricating oil/gasoline blended droplet. The experimental results indicate that the evaporation process of blended droplets can be divided into three periods. The second evaporation period may be rapid evaporation or fluctuation evaporation, which is depended on ambient temperature and gasoline content. Gasoline is the main reason of bubble generation inside blended droplets. The bubble generation, puffing and micro-explosion becomes more violent with the increase of gasoline content. The blended droplet lifetime decreases with the increase of ambient temperature. The evaporation residue is a colloidal substance at low ambient temperature and it is a hard solid material at high ambient temperature.