Experimental Investigation of Performance and Emission Characteristics of a DI Diesel Engine Using Hexenal Diesel blends

The growing concern over fossil fuel depletion and stringent emission regulations has accelerated the search for sustainable alternative fuels. In this study, an experimental investigation is carried out to evaluate the performance and emission characteristics of a direct injection diesel engine using hexanol–diesel blends. The experiments are conducted on a single-cylinder, four-stroke, water-cooled diesel engine operating at constant speed under varying load conditions. Test fuels are prepared by blending hexanol with diesel in different volume proportions (5%, 10%, and 15%), denoted as H5, H10, and H15, respectively. Performance parameters such as brake thermal efficiency and brake specific fuel consumption are analysed, along with emission parameters including carbon monoxide, hydrocarbons, and nitrogen oxides. The results indicate that hexanol addition improves combustion efficiency and significantly reduces harmful emissions. Among the tested blends, H10 exhibits the best balance between performance enhancement and emission reduction, making it a promising alternative fuel for diesel engines.