Blending alternative fuels such as ethanol with conventional fuels significantly alters their evaporation properties, directly impacting combustion behavior. To better understand the complex dynamics of preferential evaporation in engine sprays, real-time monitoring of concentration changes in single droplets is essential. In this work, a combined Raman spectroscopy and shadowgraphy approach was employed to study the evaporation behavior of acoustically levitated ethanol/isooctane fuel mixtures.
For the first time, simultaneously measured surface regression rates and time-resolved concentration profiles were provided for these fuel blends. The results demonstrate the non-ideal evaporation characteristics of the mixture and, in particular, reveal the transition between isooctane and ethanol enrichment driven by azeotrope formation.
The publication is available at: https://authors.elsevier.com/sd/article/S0016-2361(26)00793-3
