Abstract
In this study, to clarify the relationship between fuel film formation and wall characteristics such as surface roughness and thermal conductivity, fuel films formed on various walls (aluminum and quartz glass plates) by wall spray impingement were investigated. Iso-octane was injected by GDI injector set above 30 mm from the wall. Film behavior captured by a high-speed camera was analyzed to obtain a film area on the wall. The fuel film behavior was investigated under different surface roughness (Ra = 0.45 μm-17.1 μm) and various surface temperature conditions (room temperature-200°C). As a result, the fuel film area decreased with an increasing of surface roughness. Evaporation lifetime of fuel film on the aluminum plate (high thermal conductivity) was shorter than that on the quartz glass plate (low thermal conductivity).
