In a study in the journal Fuel, researchers in India report that diesel modified with nanoparticles of aluminum (Al), iron (Fe) or boron (B) reduced specific fuel consumption by up to 7% compared with standard diesel. These “nano-fuels” showed reduced ignition delay, and longer flame sustenance. Emissions of CO and hydrocarbons were reduced, however NOx marginally increased.
To study burning characteristics, engine performance and emission parameters, the team formulated the test fuels by sonicating nanoparticles of aluminum (A1), iron (F1) and boron (B1) in base diesel for use in a single-cylinder Compression Ignition (CI) engine.
These fuels showed reduced ignition delay, longer flame sustenance and agglomerate ignition. Study of engine performance at higher loads revealed drop in peak cylinder pressures and reduction of 7% in specific fuel consumption for A1 as compared to diesel.
Improved combustion rates raised exhaust gas temperatures by 8%, 7% and 5% leading to increased brake thermal efficiencies by 9%, 4%, and 2% for A1, F1, and B1 respectively, as compared to diesel at maximum loading conditions. Volumetric reduction of 25–40% in CO emission, 8% and 4% in hydrocarbon emission was measured when the engine was fueled with A1 and F1 respectively as compared to emissions from diesel. However, elevated temperatures resulted into marginal rise in NOx emission.—Mehta et al.
Rakhi N. Mehta, Mousumi Chakraborty, Parimal A. Parikh (2014), “Nanofuels: Combustion, engine performance and emissions,” Fuel, Volume 120, Pages 91-97 doi: 10.1016/j.fuel.2013.12.008