Experiments on macroscopic spray characteristics of diesel-ethanol with dispersed cerium nanoparticles

In this study, an experiment of macroscopic spray performance of stabilized nanofuels under high injection and ambient pressure is conducted on a Common rail direct fuel injection. The tested nanofuels have been prepared by DE20 (20% ethanol, 80% diesel by volume) blends with nano-CeO2 at 25 ppm(DE20Ce25), 50 ppm(DE20Ce50),100 ppm(DE20Ce100) respectively. Furthermore, appropriate amount of CTAB whose weight is equal to CeO2 and 2%vol 1-decanol were added as surfactant additive. All tested fuels were ultrasonically oscillated at a frequency of 40 khz for 45min in order to enhance their stability. The macroscopic spray characteristics of diesel-ethanol with dispersed cerium nanoparticles have been measured using the optical diagnostic techniques of shadowgraph. Comparing with those the pure diesel(D100), the spray penetration of DE20, DE20Ce25, DE20Ce50, DE20Ce100 increased by -3%, -1.8%, -0.3% and 9.5%, while the spray cone angle increased by -3%,4%,2.8% and 12.5% as well as spray area increased by -3%,-1.3%,0.6% and 31% respectively. The addition of nanoparticles also enhances the instability of fuel and shortens the crucial breakup time. In addition, the influence caused by increasing viscosity and surface tension are balanced by the disturbance. Furthermore, the macroscopic spray characteristics of DE20Ce50 show little difference with the pure diesel which means it can be a promising alternative fuel for CI engine with no required modification. (C) 2020 Published by Elsevier Ltd on behalf of Energy Institute.