Optical investigation on combustion and soot formation characteristics of isopropanol‐butanol‐ethanol (IBE)/diesel blends

Abstract

Abstract Isopropanol‐butanol‐ethanol (IBE) is considered to be a promising alternative fuel for diesel to reduce soot emissions. However, currently researchers have not yet revealed its soot formation processes. In this regard, the forward illumination light extinction (FILE) technology was used to investigate the soot formation process of IBE/diesel blends. Diesel containing 50% of IBE in volume (IBE50), pure IBE (IBE100), and diesel were tested. The experimental results show that soot formation regions for the tested fuels are greatly affected by the ambient conditions. The lower the ambient temperature is, the smaller the soot formation region is. Besides, a low ambient temperature coupled with a small ambient oxygen concentration may further reduce soot formation regions of the tested fuels. Results also show that soot formation regions of IBE50 and IBE100 are obviously smaller than that of diesel. In most test conditions, the head of soot formation regions for IBE50 and IBE100 exhibits as a thin strip. Furthermore, soot formation duration and intensity of IBE50 and IBE100 are obviously small in comparison with diesel, especially at low ambient temperature. The results of this study indicate that when IBE is directly blended with diesel, it is able to reduce soot emissions.

Keywords

• combustion
• forward illumination light extinction (FILE)
• IBE/diesel blends
• isopropanol‐butanol‐ethanol (IBE)
• soot formation process