A Study on the Performance and Emission Characteristics of a Diesel Engine Operated with Ternary Higher Alcohol Biofuel Blends

Abstract

This study focused experimentally on the evaluation of a higher alcohol biofuel utilization with diesel fuel in a compression ignition engine. To this effect, two different ternary higher alcohol biofuel blends with different percentages by volume were used, i.e., DA5 (85% diesel + 5% butanol +5% pentanol + 5% hexanol) and DA10 (70% diesel + 10% butanol + 10% pentanol + 10% hexanol). The performance and emission results were compared against reference standard diesel fuel. Experiments revealed the brake power (BP) values of the engine to be reduced due to the lower calorific value of the alcohols. In addition, this phenomenon led to increased levels of brake-specific fuel consumption (BSFC), which resulted in a higher fuel consumption to obtain unit power. Regarding emissions, carbon monoxide (CO) was reduced as a result of the additional oxygen content of alcohols, which triggered the more oxidized CO with oxygen. The results regarding unwanted nitrogen oxides (NOx) emissions were also attractive according to the alcohol utilized. Considerable reductions were obtained with alcohol mixtures when compared to diesel fuel, which can be explained by the reduced combustion temperatures in the cylinder, given the higher latent heat in the evaporation of alcohols.