The combined effect of water and nanoparticles on diesel engine powered by biodiesel and its blends with diesel: A review

In recent years, the shortage of fossil oil resources and environmental pollution problems have prompted people to look for new clean fuels to replace fossil diesel. Biodiesel has received much attention due to its environmental friendliness, renewable features and wide range of sources. Unfortunately, the use of biodiesel often causes higher NOx emissions. Water, as a fuel additive, can reduce the combustion temperature of the fuel, thus reducing NOx emission levels. However, the addition of water brings some new problems, such as the increase of CO as well as HC emissions. The nanoparticle is expected to improve this problem due to its higher area-tovolume ratio and good catalytic properties. Therefore, it is particularly important to investigate the improvement of the performance of biodiesel and its blends with diesel by nanoparticles and water. This study aims to review the effect of the combined action of water and nanoparticles on diesel engines (i.e., combustion performance and emission). The article first reviews the preparation of nanoparticles blended water-emulsion fuel and many factors affecting the fuel stability are summarized. The article then summarizes the effect of water on diesel engines and discusses the effects of metal and non-metal nanoparticles combined with water additives on diesel engines, respectively. Finally, general conclusions and future proposed research work are outlined.

Automated summary

In recent years, the search for new clean fuels to replace fossil diesel has become crucial due to the shortage of fossil oil resources and environmental pollution problems. Biodiesel has gained attention for its environmental friendliness, renewable features, and wide range of sources. However, the use of biodiesel often leads to higher NOx emissions. Water, as a fuel additive, can lower the combustion temperature and reduce NOx emissions but also brings new challenges like increased CO and HC emissions. Nanoparticles are expected to address these issues with their higher surface area-to-volume ratio and catalytic properties. Therefore, it is important to investigate the effects of nanoparticles and water on the performance of biodiesel and its blends with diesel.