Numerical Study on Internal Nozzle Flow Characteristic of Injector under Hot Fuel Conditions

Cavitation is a complicated multiphase phenomenon which leads to turbulence in fluid flows. The presence of cavitation and turbulence in a diesel injector nozzle has an effect on the subsequent spray characteristics. However, the mechanism of the flow dynamics is unclear because of the complexities of the nozzle flow. Meanwhile, there is few data exist about injector-body temperatures representative of diesel engine operation which can lead to phase change due to fuel flash boiling upon injection. Therefore, it is important to study the effect on internal nozzle flow characteristic. This paper mainly analyzed results of temperature and pressure conditions on internal nozzle flow characteristic. Diesel was simulated at 300,340,360,380,390K temperature for inlet pressure of 0.2 and 0.3MPa while the back pressure is 0.1MPa. Mass flue rate and the average velocity were also performed, and the Weber and Ohnesorge number were considered in the analysis.