Performance, combustion and emission characteristics of variable compression ratio engine using waste cooking oil biodiesel with added nanoparticles and diesel blends

The present experimental work is carried out to analyse the performance, combustion, and exhaust emission characteristics of variable compression ratio (VCR) diesel engine using blended biofuel (B20) with nanoadditives. Transesterified biodiesel was prepared from waste cooking oil (WCO). The cerium oxide nanoparticles (CERIA) were produced and categorized by precipitation technique, SEM and XRD analysis. These nanoadditives mixed with biofuel blend by magnetic stirrer and then by ultrasonication. The test procedure was carried out under the following fuel blends: 20% of biodiesel added to 80% diesel (B20), 15ppm, 30ppm, 45ppm, 60ppm and 75ppm cerium oxide nanoparticles added with B20 blend (diesel, B20, B20+CERIA15, B20+CERIA30, B20+CERIA45, B20+CERIA60, B20+CERIA75). The engine was operated at fixed compression ratio 20:1 and constant speed at various load conditions 0%, 25%, 50%, 75% and 100%, and results were compared to diesel at 100% load. The improvement in B20 fuel characteristics was observed by adding cerium oxide nanoparticles. The outcomes indicate better improvement in the blended sample of B20+CERIA45 ppm with brake thermal efficiency increased by 3.62% and specific fuel consumption decreased by 3.3% than the neat diesel. Presence of added particles gives better atomization which prompts total burning in the combustion chamber and builds up the amplified pressure data. The emission of CO and HC outflow dimnishes by the addition of CERIA nanoparticles in blended biofuel. Additionally, there is a reduction in NOx by expanding the CERIA dosage in the fuel mixer. This occurs due to CERIA particles presented in a fuel blend behaving as an oxygen buffer and engaging the O-2 for decreasing the NOx formation.