Effects of silicon dioxide nanoparticles on the performance and emission features at different injection timings using water diesel emulsified fuel

In this work the investigations were conducted to examine the effects of silicon dioxide (SiO2) nanoparticle on water diesel emulsified fuel (WDEF) for diesel engine at various injection timings. The base fuel used was D94W5S1 (Diesel 94%, water 5%, and SPAN-80 1%) in which SiO2 nanoparticles were added in the varying dosages of 25, 50, 75, and 100 ppm. The test fuels of WDEF-SiO2 were prepared with the magnetic stirrer and ultrasonication technique and experiments were conducted with the constant speed of 1500 RPM, compression ratio 18 and 23 degrees bTDC injection timing. From the experiments, the test fuel with 50 ppm dosing D94W5S1-Si50 was found to be optimal as it results in a reduction of 52.52%, 29.32%, 69.69%, and 64.28% for NOx, smoke opacity, hydrocarbon, and carbon monoxide emissions respectively as compared to neat diesel at full load condition. Further, the optimal fuel was tested for different injection timing of 19 degrees bTDC, 21 degrees bTDC, 23 degrees bTDC, and 25 degrees bTDC. The results revealed that with the advancement of injection timing to 25 degrees bTDC, brake thermal efficiency increases by 2.61%, brake specific fuel consumption diminishes by 3.7%. Except NO emissions, which rises by 6.63%, other emissions of smoke opacity, hydrocarbon, and carbon monoxide reduces by 7.41%, 10%, and 50% respectively as compared to 23 degrees bTDC. Finally, it can be concluded that WDEF incorporated with optimal dosing of silicon dioxide nanoparticle at advanced injection timing remarkably reduces the emissions and enhances the performance features.