Comparative combustion, emission, and performance analysis of a diesel engine using carbon nanotube (CNT) blended with three different generations of biodiesel.

Abstract

Nano-additives are being employed in successive generations of biodiesels to increase the performance characteristics and output of diesel engines. In this study, the impact of mixing carbon nanotubes (CNT) with three different generations of biodiesel in a diesel engine is assessed. With 100 ppm of CNT nanoparticles mixed together, pure biodiesels made from first-generation oil (soybean), second-generation oil (neem), and third-generation oil (Nannochloropsis oculata microalgae) are used for the analysis. With an engine load ranging from 0 to 100%, a one-cylinder, four-stroke, direct injection diesel engine is employed. The engine has a water-cooling system, a compression ratio of 17.5:1, and a fuel injection angle of 23° before TDC. The evaluated engines' improved performance and lower emissions serve as proof of the outcomes. The results are evidenced by the lower emissions and higher performance of the tested engines. The biodiesel containing CNT nanoparticles enhanced the cylinder pressure by 0.8-10.69%, the heat release rate (HRR) by 6.38-21.69%, and the brakethermal efficiency (BTE) by 0.32-1.62%. Subsequently, it reduced the brake-specific fuel consumption (BSFC) by 2.53-8.13%, the brake-specific energy consumption (BSEC) by 1.07-3.77%, the smoke opacity (BSN) by 6.26-12.85%, the particulatematter (PM) emissions by 11.04-18.33%, and the carbon dioxide (CO2) emissions by 2.53-8.14% at full engine load. However, an increase in 13.62-18.37% nitrogen emissions (NOx) emissions is also observed with the addition of CNT at 100% load. The investigation supports the use of CNT nano-additives in diesel engines for improved performance and reduced emissions.