Optimisation and environmental analysis of waste cashew nut shell oil biodiesel/cerium oxide nanoparticles blends and acetylene fumigation in agricultural diesel engine

This research aims to comprehensively analyse the performance, combustion, and emissions of cashew nut shell oil (CNSO) biodiesel blends with cerium dioxide (CeO2) nanoparticles and acetylene injection in agricultural diesel engines. The test fuels are diesel, CNSO biodiesel, B50 (50% CNSO biodiesel + 50% diesel), and CeO2 blends (diesel + CeO2 25 ppm, CNSO biodiesel + CeO2 25 ppm, B50 + CeO2 25 ppm). Acetylene was injected into the intake manifold at 3 lpm and 6 lpm. The experimental result revealed that the engine brake thermal efficiency (BTE) showed a 1.38% decrease when CNSO biodiesel was used instead of diesel fuel. However, the addition of CeO2 nanoparticles and acetylene to diesel fuel had a significant improvement in BTE. Furthermore, the injection of acetylene improved combustion, resulting in a 10.42% increase in peak pressure (Pmax) and a 3.18% increase in BTE. Nitrogen oxide (NOx) emission was lower for diesel with 6 lpm acetylene injection than other test fuels. Additionally, adding CeO2 nanoparticles to CNSO biodiesel reduced hydrocarbon (HC) and carbon monoxide (CO) emissions by 5.92% and 3.3%, respectively, compared to pure diesel. The investigation utilised Response Surface Methodology (RSM) to analyse the effects of various input parameters on engine performance and emissions. The optimised result indicated that the combination of CeO2 blended with CNSO fuel yielded the most favourable engine performance. Furthermore, the validation experiments confirmed the reliability of the optimised result, as the predicted values closely matched the experimental values. This work concluded that using CNSO biodiesel with CeO2 nanoparticles and acetylene injection suits agricultural diesel engines.