Amplifying performance, combustion, and emission characteristics of a CRDI engine using diesel-WCO methyl ester-dyglyme ternary fuel blends with carbon nanotubes

The present study investigates the performance, combustion, and emission characteristics of various fuel formulations, including neat diesel (D100), a biodiesel blend (WCO20: 20% waste cooking oil methyl ester and 80% diesel), a Ternary Fuel (TF) blend composed of 20% WCOME, 70% diesel, and 10% diglyme (DGM), and TF blends doped with Carbon Nanotube (CNT) nanoparticles at concentrations of 25, 50, and 75 mg/L. All fuel samples were evaluated using a twin-cylinder, four-stroke, Common Rail Direct Injection (CRDI) compression-ignition engine. Biodiesel is prepared from WCO using the well-known transesterification process. The NPs included in TF samples are found to be stable and confirmed by characterization (FESEM, HRTEM, FTIR, and UV Spectroscopy). The performance parameters, such as Brake Thermal Efficiency (BTE), are increased by 15.15%, and Brake Specific Fuel Consumption (BSFC) is decreased by 16.5%. Moreover, the combustion parameters, including Cylinder Pressure (CP), Net Heat Release Rate (NHRR), Mass Fraction Burning (MFB), and Cumulative Heat Release Rate (CHRR), are improved due to catalytic activity, higher evaporation capacity of DGM, improved rate of reaction, and oxygen content in the fuel blend. The emission characteristics, including Carbon monoxide (CO), Carbon dioxide (CO2), Hydrocarbons (HC), and Nitrogen Oxides (NOx), are reduced by 17.5, 22.27, 22.09, and 25.8% at higher load for the TF+CNT50 mix, respectively. The outcomes show the feasibility of DGM and CNT NPs as suitable additives in the WCO20 sample for lower emission parameters without compromising performance and combustion characteristics.