Unveiling the Role of Nanoparticles in Biodiesel Blends: A Comprehensive Energy‐Exergy‐Sustainability Analysis for CI Engine Optimization

ABSTRACT The unsatisfactory engine performance can be enhanced by the fuel reformulation technique in which the nano additives are included in the B20 (20% of methyl ester mixed in 80% of diesel) sample. In the present study, a novel nano additive such as Aluminium oxide (Al 2 O 3 ), Graphene Oxide (GO), and Carbon Nanotubes (CNTs) are added in B20 mix (20% Vol. of Yellow Oleander Methyl Ester (YOME) is blended in 80% Vol. of standard diesel) and employed on a single cylinder, four stroke, diesel engine. The study is focused on evaluating the Energy (E), Exergy (ex), and sustainability index (SI) through the energy and exergy distributions using first and second laws of Thermodynamics (TD) for the prepared fuel samples, including D100, B20, B20A50, B20GO50, and B20CNT50. The engine operated with the prepared blends at standard conditions such as Compression Ratio (CR) (17.5:1), Rated speed (1500 rpm), Injection Timing (IT) (23° bTDC), and Injection Pressure (IP) (220 bar). The nano‐assisted fuel samples showed enhanced performance characteristics (Brake Thermal Efficiency (BTE) increased by 15.94%, and Brake Specific Fuel Consumption (BSFC) reduced by 20.5%) Energy, and Exergy efficiencies (η E , η ex ), SI, and Exergy Performance Coefficient (EPC) by 33.6, 23.6, 7.14, and 13.7, %, respectively, for B20CNT50 blend at higher Brake Power (BP). The blend B20CNT50 proved to be a more promising fuel sample than the remaining fuel mixtures in a significant variation in engine performance, Energy (E), exergy (ex), and SI. It is not just a promising alternative but also a more sustainable and effective energy source to use with nano‐assisted biodiesel‐diesel blends. This article recommends more investigations and research into engine optimization and the development of sustainable energy alternatives.