IMPACT OF ANTIOXIDANT–NANOPARTICLE ADDITIVES ON COMBUSTION, PERFORMANCE, AND EMISSION CHARACTERISTICS OF A BIODIESEL-FUELED CRDI DIESEL ENGINE

This study investigates the effect of antioxidant additives on the performance and emission characteristics of a Common Rail Direct Injection (CRDI) diesel engine fuelled with biodiesel blends. Biodiesel derived from Madhuca indica (Mahua) oil was blended with conventional diesel in different proportions (B10, B20, and B30). To enhance oxidative stability and control NOx emissions, two antioxidants, Butylated Hydroxytoluene (BHT) and Tert-Butylhydroquinone (TBHQ), were added at concentrations of 1000 ppm and 1000 ppm. Experiments were conducted on a single-cylinder, four-stroke, water-cooled CRDI engine at a constant speed of 1500 rpm under varying load conditions. The results showed that the addition of antioxidants improved brake thermal efficiency (BTE) and reduced brake-specific fuel consumption (BSFC) compared to untreated biodiesel blends. A notable reduction in NOx and smoke opacity was achieved with TBHQ, while CO and HC emissions exhibited a marginal increase. The optimal performance and emission trade-off was obtained with the B20 + TBHQ (1000 ppm) blend, demonstrating the potential of antioxidant-treated biodiesel as a sustainable and cleaner fuel for CRDI diesel engines.