Influence of Ethanol Blended Diesel Enriched with Hydroxy Gas in Dual-Fuel Mode on Common Rail Direct Injection Engine

Abstract

This study investigated the impact of dual-fuel operation using ethanol-blended diesel fuel enriched with hydroxy gas on CRDI engine performance, combustion, and emission characteristics. Neat diesel fuel was used to run the engine, along with a 20% volume fraction of an ethanol-diesel mixture that had been enhanced with three distinct streams of hydroxy gas, namely 1, 1.5, and 2 LPM. Hydroxy gas was generated by an electrolysis technique using a plate-type dry cell electrolyser (316 L stainless steel) in the presence of a NaOH catalyst. Compared to E20 (Ethanol 20%) fuel, HHO gas enrichment with lower proportions of ethanol blend E20 + 2LPM had a 2.74% increase of BTE and a 5.89% decrease of BSEC at a 5.02 bar BMEP condition. Similarly, HC, CO, and smoke emissions decreased by 4.61%, 5.19%, and 3.1%, while NOx emissions and EGT increased by 3.22% and 3.06% compared to E20. With the addition of HHO gas, combustion characteristics such as HRR, CP, and ignition delay improve while the combustion duration increases. At maximum BMEP, cylinder pressure and heat release rate increase by 3.18% and 6.58% for E20 + 2LPM HHO, respectively. It was found that the 20% volume of the ethanol-diesel blend, with 2 LPM of hydroxy gas, positively affects engine characteristics.