Journal of the Korean Society of Propulsion Engineers (한국추진공학회지)

The Korean Society of Propulsion Engineers (한국추진공학회)
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A Numerical Study of the Flow Characteristics and Starting Pressure of a Center Body Diffuser According to the Center Body Position and Cone Angle

Center Body 위치와 Cone 각도에 따른 Center Body Diffuser의 유동특성 및 시동에 대한 수치적 연구

  • Lee, Sung Hun (School of Mechanical Engineering, Chungnam National University) ;
  • Park, Jin (School of Mechanical Engineering, Chungnam National University) ;
  • Kim, Hong Jip (School of Mechanical Engineering, Chungnam National University)
  • Received : 2019.06.07
  • Accepted : 2019.09.14
  • Published : 2019.10.01
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Abstract

In this study, flow characteristics and the starting pressure of a center body diffuser (CBD) were analyzed at various center body (CB) positions and cone angles. According to the CB position, the location of oblique shock moved to the front from behind the CB cone with an increase in the flow momentum. Additionally, when a strong oblique shock occurred, the direction of supersonic flow was affected and induced to diffuser wall. As a function of different cone angles for the oblique shock, the starting pressure of the CBD was significantly affected.

Center Body Diffuser (CBD)의 Center Body (CB) 형상에 의한 유동 특성 및 시동압력을 해석하였다. CB 위치와 Cone 각도의 변경을 통해 초음속 유동 특성 및 시동압력을 비교하였다. CB 위치를 변수로 하여 Diffuser 해석한 결과, 유동의 모멘텀의 형성에 따라 강한 경사충격파의 발생위치가 달라지는 것을 확인하였다. 또한 경사충격파가 발생할 경우, 초음속 유동의 방향이 디퓨저 벽면으로 유도되는 것을 확인하였다. Cone 각도 변화에 따른 경사충격파의 각도 차이로 인하여, CBD의 시동압력이 영향을 받는 것을 확인하였다.

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References

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