Study on the combustion and emission characteristics of a compression ignition engine using diesel/ethanol blend with carbon nanoadditives

Abstract

This article focuses on the effects of adding different types (graphene oxides, multi-layered graphene oxides, multi-walled carbon nanotubes) and dosages (25 ppm, 100 ppm) of renewable carbon nanoparticles to the diesel/ethanol blend towards the combustion and emission characteristics of a compression-ignition engine. The research showed that a shortened ignition delay was brought about due to the presence of carbon nanoparticles, with the most pronounced effect achieved by multi-walled carbon nanotubes. Regarding in-cylinder combustion, the inclusion of carbon nanoparticles induced an enhancement to the combustion progress, associated with increments in peak cylinder gas pressure and peak heat release rate and a decrement in combustion duration, most notably accomplished by graphene oxides. Moreover, the engine exhibits lower fuel consumption and better fuel utilization based on the carbon nanoparticles addition, where the nano-fuels with graphene oxides possess the minimum brake specific fuel consumption and maximum brake thermal efficiency. Concerning the abatement effect, by applying carbon nanoparticles, emissions of CO, HC and soot were decreased by 37.95 %, 45.18 % and 47.83 %, respectively, however, a slight increase in NOx emissions also occurred. In particular, multi-walled carbon nanotubes offered the most significant mitigations in CO and HC, while graphene oxides achieved the greatest abatement in soot emissions.