Combustion characteristics and emissions of a common rail diesel engine using nanoparticle-diesel blends with carbon nanotube and molybdenum trioxide

Highlights: • CNT-diesel was ignited earlier than MoO₃-diesel. • CNT-diesel presented lower heat release peaks than MoO₃-diesel. • CNT-diesel showed better fuel economy than MoO₃-diesel. • CNT-diesel reduced more HC, CO, NO_x and smoke emissions than MoO₃-diesel. -- Abstract: One of the most important challenges in engine applications is to reduce emissions. Improving fuel quality by adding nanoparticles is an appropriate method to meet this challenge. In the study, two typical nanometre materials, i.e., CNT (which is non-metallic and possesses excellent thermal conductivity) and nano-MoO₃ (which represents the metal oxides and owns favourable catalytic function), were examined comparatively as additives in neat diesel. CNT-diesel and MoO₃-diesel nano-fuels were prepared using the appropriate physical and chemical dispersion methods. Experiments were performed in a single-cylinder common rail diesel engine to investigate and compare the combustion and emissions performances of nano-fuels with neat diesel. It was found that both CNT-diesel and MoO₃-diesel achieved better performance in fuel economy, combustion and emissions than neat diesel. These outcomes may be due to the excellent thermal conductivity and surface deficits of CNT and the good catalytic oxidation function of MoO₃. In addition, CNT-diesel was found more promising, because it seems to produce more benefits in promoting combustion efficiency and emissions reduction than MoO₃-diesel.