Flame Characteristics of Gasoline and a Water-in-Gasoline Mixture under a Controllable High-Temperature Thermal Atmosphere

[Image: see text] This study explores the flame characteristics of gasoline and a water-in-gasoline mixture and provides some optimization suggestions for the control strategy of water-in-gasoline mixture injection in the internal combustion Rankine cycle engines. The influences of co-flow temperature, injection pressure condition, and water content on the flame characteristics were investigated under a controllable high-temperature thermal atmosphere, including flame pattern, liftoff height, brightness, and local peak temperature distribution. Results obtained show that the water content has the most significant effect on the flame characteristics. The flame pattern gradually changes from slender to lumpy as the water content rises, while the high-temperature zone increases and becomes uniform. There is an appropriate water content range of 10–20% in which the flame characteristics are generally better. Furthermore, as the water content increases from 20 to 30%, the flame characteristics deteriorate, with a sharp decrease in the maximum flame temperature and brightness.