Analysis on Evaporation Characteristics of Palm Oil Biodiesel: Effect of Substrate’s Inclination Angle

The purpose of this study is to investigate the evaporation characteristics of biodiesel-diesel blends with different mixing ratios by applying the hot surface deposition test (HSDT) method. In this study, diesel fuel (DF) was blended with pure palm oil biodiesel (B100) to produce fuel with different blend ratios (B10, B20, B30, B40, B50). The test fuels were impinged on a horizontal (0°) and inclined (5° and 10°) heated aluminum alloy plate with various surface temperature. Generally, the evaporation lifetime and maximum evaporation point (MEP) were higher for fuel with higher biodiesel content. However, the droplet lifetime and MEP decrease as the inclination angle of the plate increases. This is due to the droplet sliding which provided larger surface area for evaporation process, resulting in shorter evaporation time. Furthermore, fuel droplets were observed to slide down off the inclined plate within the Leidenfrost temperature region, and this occurrence was more prominent at higher inclination angle and for fuels with lower biodiesel content.