Impact of Change in Acoustic Parameters on the Particle Emissions from Blends of RME and Isopropanol

The particle emissions from diesel engines are a major environmental problem due to their harmful effects on air quality and human health. This article investigates the underlying acoustic parameters that determine the efficiency of reducing the fine particles through agglomeration. The impact of a change in frequency and voltage on the acoustic waves through the excitation source is researched and analyzed. Three blends of rapeseed methyl ester and isopropanol (RME95I5, RME90I10, and RME80I20) are used for experiments to study the combined benefit of oxygen-rich blends. The exhaust particles are measured before and after the exposure to acoustic waves operated at a varying voltage and frequency ranges. The fine particle reduction with a simultaneous increase in 5–10 µm particles is found to be better at the lower frequency due to the severe acoustic attenuation at the higher frequency. With the increase in voltage to 200 V, the reduction in fine particles and the simultaneous increase in coarse particles are comparatively less. The change in voltage induces an increase in sound intensity, which slows down the growth of agglomerates. The study presents the critical information necessary to use acoustic waves to reduce particle pollution using conventional filters, including the mechanisms by which sound intensity affects particle size distribution and the effectiveness of this method in various environmental conditions.