Assessing the Effect of Aluminium Oxide Nanoparticle Additives on Biodiesel Combustion in Marine Diesel Engines

The increases in annual ship exhaust emissions have prompted the shift towards adopting alternative energy sources. Biodiesel is a suitable substitute fuel for marine engines that does not necessitate engine alterations. Biodiesel is renewable, environmentally friendly, and plant-based with biodegradable properties. The fuel is also non-toxic and oxygenated and shares similar characteristics with diesel fuel. Nonetheless, biodiesel fuel exhibits slightly reduced performance compared to diesel primarily due to its lower energy content. This study aims to evaluate the combustion attributes of a marine diesel engine employing palm biodiesel fuel incorporated with aluminium oxide (Al2O3) nanoparticle additives. A B20 biodiesel fuel was blended with 50, 100, and 150 ppm Al2O3 nano additives. The engine combustion parameters, in-cylinder pressure, heat release rate (HRR), mass fraction burned, and ignition delay were analysed and compared to the B20 fuel without additives. Adding Al2O3 nano additives to the B20 biodiesel blend improved the engine combustion characteristics. The optimal performance was recorded by the blend incorporating 150 ppm nanoparticles. The in-cylinder pressure and HRR peaks also improved by 5.41 to 15.1% and 4.69 to 16.9%, respectively, compared to the other B20 fuel blends. Furthermore, the B20 mixed with Al2O3 documented a more rapid mass fraction burned rate, resulting in a shorter ignition delay of approximately 5 CA°. In addition, the amount of oxygen in biodiesel blended with Al2O3 nano additives has improved engine combustion compared to B20 fuel. The present study demonstrated that adding Al2O3 nano additives to palm biodiesel fuel significantly enhanced engine combustion attributes, thus highlighting its potential to reduce reliance on petroleum-based fuels and provide sustainable fuel alternatives for marine diesel engines.