난류 횡단류에 수직 분사 되는 액주의 분열 및 기화 특성에 관한 LES

LES of Breakup and Atomization Characteristics of a Liquid Jet into Cross Turbulent Flow

  • 양승준 (한국항공대학교 항공우주 및 기계공학과) ;
  • 구자예 (한국항공대학교 항공우주 및 기계공학부) ;
  • 성홍계 (한국항공대학교 항공우주 및 기계공학부) ;
  • 투고 : 2009.12.10
  • 심사 : 2010.03.27
  • 발행 : 2010.04.30

초록

난류 유동장으로 분사되는 액체 제트의 액주 분열과 액적 미립화 현상에 관한 LES를 수행하였다. 기체상태의 공기 유동해석에 Eulerian 해법을 사용하고, 액적 추적을 위하여 Lagrangian 해법을 사용하여 기체-액체간 이상유동(two phase flow) 해석을 수행하였다. 액적 분열 과정 모사에 blob-KH 분열 모델을 적용하여 액주와 액적의 분열이 관찰되었다. 일정한 공기 유동 조건에서 액체 분사 속도 변화를 통한 액체-기체 운동량 플럭스 비의 변화에 따른 액체 제트의 침투깊이를 조사하였으며 실험결과와 유사함을 알 수 있었다. 분사 제트의 분열에 따라 유동장에 존재하는 액적의 분포를 Sauter 평균 입경(SMD)의 분석을 통해 수행하였다.

LES(Large eddy simulation) of breakup and droplet atomization of a liquid jet into cross turbulent flow was performed. Two phase flow of gas and liquid phases were modeled by the mixed numerical scheme of both Eulerian and Lagrangian methods for gas and liquid droplet respectively. The breakup process of a liquid column and droplets was observed by implementing the blob-KH wave breakup model. The penetration depth into cross flow was comparable with experimental data for several variants of the liquid-gas momentum flux ratio by varying liquid injection velocity. SMD(Sauter Mean Diameter) distribution downstream of jet was analyzed.

키워드

참고문헌

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