Effect of hydrogen and multiwall carbon nanotubes blends on combustion performance and emission of diesel engine using Taguchi approach

Abstract

The analysis of optimum engine conditions operating under hydrogen and multiwall carbon nanotubes (MWCNTs) blends using the Taguchi L16 approach were examined. The effect of hydrogen (10%, 20%, and 30%) and MWCNTs (30 ppm, 50 ppm, and 80 ppm) with different fuel blend proportions were evaluated at different engine loads of 25%, 50%, 75%, and 100%. Further, the influence of ignition pressure was evaluated at four intervals of 180 bar, 200 bar, 220 bar, and 240 bar. In addition, the ignition timing varied at different intervals of 210bTDC, 230bTDC, 270bTDC and 310bTDC, respectively. TaguchiL16 approach was designed according to the combinations of the array, including load, hydrogen, MWCNTs, ignition pressure, and timing with four optimal conditions. Results revealed that the L16 orthogonal array was a suitable method to find the optimized working conditions of the diesel engine for higher performance and less emission of NOx, HC, CO, and CO2. Compared to neat diesel, the addition of hydrogen and MWCNTs reduces the emission with improved brake thermal efficiency. The effects of the optimal factors were further analyzed using ANOVA. From the ANOVA results it is evident that, the addition of hydrogen and MWCNT advances the performance and emission characteristics. Moreover, results showed improved brake power by 13% and reduced brake specific fuel consumption by 8% at full engine load conditions. 22%, 20%, 8%, and 47% emission reductions of HC, NOx, CO, and CO2 were observed due to the influence of hydrogen and MWCNTs.