Effect of Nanoparticles on the Performance and Emission Characteristics of Diesel Engine Operated with Different Fuels

Thermal efficiency and fuel economy of diesel engines are better. Despite the fact, due to the depletion of world petroleum reserve and hazardous pollutant emission to the environment, there is a need to research on the improvement of performance and reduction of environmental pollution. Utilization of biofuels such as ethanol and biodiesel is a solution to substitute petro-diesel and reduce pollution. The low calorific value of biofuels makes them to have lesser performance values compared to neat diesel. To improve the performance and reduce emission, strategies of fuel modification consisting of modifying fuel characteristics to improve combustion, which leads to better engine performance, less exhaust emissions, and higher fuel economy, are required. Addition of biofuels such as ethanol to petro-diesel lowers the calorific value and the cetane number of the emulsified fuel which reduces the performance of the engine and increase fuel consumption. Adding nanoparicles in base fuel is a promising way of improving fuel properties to improve performance and decrease pollution. In this review work, the performance and exhaust emission characteristics of different nanoparticles such as CNT, MoO3, Al2O3, TiO2 ZnO, CeO2, and GQD in different base fuels are covered. The study indicated that the highest brake thermal efficiency is reported for CNT and Al2O3 nanoparticles. Al2O3, GQD, and TiO2 nanoparticles resulted in a very significant reduction of HC and CO emission. Regarding NOx emission, inconsistent reports are seen from the papers covered in this review. Majority of the research indicated there is a reduction of NOx emission; however, some of the reports which are done by CNT, Al2O3, GQD showed increasing NOx emission relative to the base fuel.