A Fundamental Study on Suppressing the Bubbling in the Injector of LPDi Engine by High Pressurization of Fuel

연료 고압화에 의한 LPDi 기관의 인젝터 내 기포발생 억제에 관한 기초 연구

  • Noh, Ki-Chol (Department of Mechanical Engineering, Sungkyunkwan University) ;
  • Lee, Jong-Tai (Department of Mechanical Engineering, Sungkyunkwan University)
  • 노기철 (성균관대학교 기계공학부) ;
  • 이종태 (성균관대학교 기계공학부)
  • Published : 2007.05.01

Abstract

To suppress the bubble generated in the liquid LPG direct injector is the most important to develop the LPDi engine. It was found in the previous study that bubbling phenomenon in the injector of the LPDi engine is decisively influenced by pressure of fuel and temperature around the injector. Therefore, in this study, the effect on suppressing the bubbling in the LPDi injector by high pressurization of fuel is analyzed and the spray characteristics are also studied. As a result, it is found that the bubbling in the LPDi injector is radically suppressed when the pressure of fuel is over 50MPa. The bubbling is suppressed when the pressure of fuel is over 3MPa if the inserted position of the injector is considered. Also, it is confirmed that the higher the pressure of fuel is the longer spray tip penetration and is the larger spray angle. As the ambient pressure increases, spray tip penetration decreases and spray angle increases due to the increase of drag force.

Keywords

References

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