Composite materials are continuously replacing the conventional materials and alloys owing to their weight reduction. Biodegradable fiber-reinforced composite materials are one of the prime attractions to the researcher due to their easy availability and low cost. During drilling of these Natural Fiber Reinforced Plastic composites (NFRP), delamination and surface roughness are the problems encountered, which are to be minimized to get better output by adopting different cutting conditions and tools. This work aims at the drilling of naturally available coir fiber-reinforced composite materials by using a multifaceted drill bit. Material thickness, spindle speed, feed rate, and multifaceted bit diameter are input against the output delamination. After modeling of the output result, a sensitivity analysis tool is introduced to rate the input factor to minimize delamination. SEM images are used to analyze the fracture morphology.

ABSTRACT. Energy demand increases day by day due to the present technological scenario and fossil fuels are also depleting gradually. Therefore, the necessity came into the researchers to identify an alternative renewable resource for compensating the energy demand. The biodiesel appeared to the researchers as an important resource due to its characteristics and ability to compensate for the energy demand. However, some additional improvements are required for the efficient performance of the biodiesel, such improvement is achievable by the blending of an efficient additive with the biodiesel. The present study predominantly focuses to investigate the performance of the biodiesel with two different additives such as cerium oxide nanoparticles and ethanol. The neem (Azadirachta indica) oil has been selected as feed stock. The cerium oxide nanoparticles are prepared using the green synthesis process. Four various fuel samples are prepared to examine the effect of additives, (i) PB (pure biodiesel), (ii) BCe (PB+100 ppm CeO2), (iii) BE (90% biodiesel+10% ethanol) and (iv) BCeE (90% biodiesel+100 ppm CeO2+10% ethanol). From the experimentation, it is observed that the fuel BCeE achieves the better performance due to the oxygen buffering characteristics and improvement in the atomization by the additives.   KEY WORDS: Additives, Nanoparticles, Neem oil, Emission, Combustion, Heat release rate   Bull. Chem. Soc. Ethiop. 2023, 37(2), 477-490.                                                                DOI: https://dx.doi.org/10.4314/bcse.v37i2.16