Evaporation and combustion characteristics for a droplet of lubricating oil and gasoline

The droplet suspension technology is used to study the effects of ambient temperatures (from 673 to 873 K) and gasoline blending ratios (from 0% to 20%) on evaporation and combustion characteristics of lubricating oil (LO), used lubricating oil (ULO) and the mixture of lubricating oil and gasoline (LO/gasoline and ULO/gasoline). The experimental results show that the evaporation process of LO80G20 (the blend of 80% LO and 20% gasoline by volume fraction) contains a transient heating period, a fluctuation evaporation period and a slow evaporation period at 673 K. The combustion process at high temperatures (from 723 to 873 K) includes an auto-ignition delay period, a combustion period and an extinction period. At the same ambient temperature, both the auto ignition delay and lifetime of ULO are shorter than those of new LO. The occurrence time and intensity of puffing for ULO are earlier and stronger than those of new LO. For the mixture of lubricating oil and gasoline (LO/gasoline and ULO/gasoline), the auto-ignition delay, droplet lifetime and the occurrence time of puffing decrease with the increase of gasoline component.