Combined effect of influence of nano additives, combustion chamber geometry and injection timing in a DI diesel engine fuelled with ternary (diesel-biodiesel-ethanol) blends

The present experimental work focuses on the combined effect of nano additives, combustion chamber geometry and injection timing in a single cylinder diesel engine fuelled with ternary fuel (diesel-biodiesel-ethanol) blends. Ternary fuel (TF) is doped with alumina nano additives and the resulting fuel is termed as high performance fuel (HPF). HPF is subjected to different combustion chamber geometries and TRCC (torroidal re-entrant combustion chamber) geometry is found to be effective among other geometries. HPF operated at TRCC chamber is subjected to four different injection timings namely, 21 degrees bTDC (HPF-TRCC21), 22 degrees bTDC (HPF-TRCC22), 23 degrees bTDC (HPF-TRCC23) and 24 degrees bTDC (HPF-TRCC24) respectively. BTE is lowered for HPF-TRCC21 and HPF-TRCC24 by 4.53% and 1.22% while highest BTE of about 33.8% is achieved for 22 degrees bTDC in comparison with other blends such as DIESEL-HCC23 (32.75%), HPF-TRCC21 (31.41%) and HPF-TRCC24 (32.53%). Lowest BSEC profile was achieved for HPF-TRCC22. HPF-TRCC22 resulted in lowered HC and CO emissions of about 9.18% and 16.83% in comparison with HPF-TRCC23. HPF-TRCC21 resulted in lowered NOx emissions by 22.53% along with higher HC and CO emissions by 6.13% and 20.51% in comparison with HPF-TRCC23. Cylinder pressure and HRR of HPF-TRCC22 stays at an acceptable range of 75.42 bar and 85.34 J/deg CA in comparison with other test blends. The DIESEL-RK theoretical simulation results are compared with the experimental study conducted at the same operating conditions and its revealed that TRCC combustion chamber geometry is better for enhanced performance and combustion characteristics. (C) 2019 Elsevier Ltd. All rights reserved.