A comprehensive review on combustion and stability aspects of metal nanoparticles and its additive effect on diesel and biodiesel fuelled CI engine

Nanofluids are described as a relatively new kind of colloidal solutions with a particle size smaller than one billionth of a meter (1-100 nm) suspended in the base fluid so as to enhance the thermophysical properties, which makes them an obvious choice for use in number of commercial applications including engineering, medical sciences, biotechnology, agriculture technology, transportation etc. With the advancement in nanotechnology during last few years, scientific community focuses on improvising combustion behavior, stability aspects, various engine performance parameters and emission characteristics of conventional diesel engine using nanoparticle laden diesel biodiesel fuel blends. Most recently few experimental works on above issues using nanosited metallic, non-metallic, organic and mixed particles in the base liquid fuel for diesel engine have appeared in the open literature. The obtained results are very encouraging due to multifold enhancement in thermo physical and chemical properties of modified fuel such as high surface to volume ratio, high reactive medium for combustion, enhanced heat and mass transport properties due to high thermal conductivity, improvement in flash point, fire point, pour point etc depending upon the type of nanoparticles used, their particle size and concentration with base fuel. Despite having all superiorities, somewhat unclear and contradictory results are found in the literature, further the experimental results of different researchers are not generalized so far as to reach at common consensus about this new approach of fuel Modification. Keeping all these facts in mind, a serious attempt has been made to summarize the important published work on combustion and stability aspects of nanoparticle laden diesel, biodiesel fuels and their blends, and its effects on fuel and engine overall characteristics with the objective to provide a pathway to conduct further research in this area for utilizing maximum potential of nanoparticle fuel emulsion technology and to provide a promising future fuel for diesel engine.