纳米氧气泡对燃料喷射喷雾过程影响的分子动力学模拟研究

In order to investigate the influence of bubbles on the injection process of bubbly flow fuel, the molecular dynamics simulation was used to simulate the process of nano oxygen bubble fuel passing from the fuel tank through the high-pressure fuel rail and finally being ejected through the injector nozzle. The results show that the stability of nano oxygen-bubble in fuel under normal temperature and pressure conditions depends on the number of gas phase molecules added. The more gas phase molecules added, the more favorable it is for the stable existence of nano oxygen-bubble. When the bubbly flow fuel enters the high-pressure rail, the nanobubble which can be stabilized in the fuel at normal temperature and pressure quickly dissolve and disappear under the influence of external high pressure conditions. When fuel is sprayed out through the nozzle of the fuel injector, due to an increase in external temperature and a decrease in pressure, gas phase molecules previously dissolved in the fuel first precipitate into bubbles, which gradually expands, eventually bursting and escaping. This process contributes to the breakup of the fuel and to the increase of oxygen concentration around the fuel, as well as to the atomization and subsequent combustion of the fuel.