Evaluation of Combustion Stability and Exhaust Emissions of a Stationary Compression Ignition Engine Powered by Diesel/n-Butanol and RME Biodiesel/n-Butanol Blends

Abstract

In recent years, the interest in renewable fuels has increased mainly due to regulations regulating the permissible limits of toxic components of exhaust gases emitted by reciprocating engines. This paper presents the results of a comparison of the effects of fueling a compression-ignition piston engine with a mixture of diesel fuel and n-butanol, as well as RME (Rapeseed Oil Methyl Esters) biodiesel and n-butanol. The tests were carried out for a constant load and a wide energetic share of fuels in the mixture. The main focus was on the assessment of combustion stability, the uniqueness of the combustion stages, and the assessment of the fuel type influence on the CA50 angle. The tests show that RME offers the possibility of efficient combustion with n-butanol with up to 80% energy share. The share of n-butanol has a positive effect on the engine’s efficiency and very effectively reduces soot emissions. Without the influence on COVIMEP, the share of n-butanol up to 40% in the mixture with diesel fuel and up to 80% in the mixture with RME was recorded. Combustion of RME with n-butanol was more stable. The share of n-butanol in the mixture with diesel fuel caused an increase in NOx emissions, and co-combustion with RME caused a decrease in emissions.