DOI QR코드

DOI QR Code

분사조건에 따른 기체/액체 동축형 인젝터의 분무특성에 관한 연구

A Study on Characteristics of Gas/Liquid Coaxial Sprays Under Varying Flow Conditions

  • 정원호 (서울대학교 대학원 기계항공공학부) ;
  • 김동준 (서울대학교 대학원 기계항공공학부) ;
  • 임지혁 (서울대학교 대학원 기계항공공학부) ;
  • 윤영빈 (서울대학교 기계항공공학부)
  • 발행 : 2005.01.01

초록

기체와 액체 추진제를 사용하는 동축형 분사기의 분무특성을 조사하기 위하여 shadow graph와 mechanical patternator, PDPA를 이용한 실험을 수행하였다. 차원해석 방법을 도입하여 운동량 플럭스 비(M)와 레이놀즈 수(Re)를 기체/액체 동축형 분무의 주요 변수로 설정하였고, 실험을 통하여 전단 및 스월 동축형 분무의 특성을 거시적 및 미시적 관점에서 비교분석하였는데, 기체 추진제의 영향력이 커지는 분사조건에서 전단 및 스월 동축형 분무의 거시적 특성이 유사해짐을 확인할 수 있었다. 또한, 본 연구에서는 미시적 분무특성에 대한 분석 결과로서 분무액적 크기와 분사조건 사이의 관계식도 제시하였다.

Characteristics of sprays injected by gas/liquid coaxial atomizers operated at atmospheric pressure are studied using shadowgraph, mechanical patternator and PDPA. The gas-to- liquid momentum flux ratio(M) and the liquid Reynolds number(Re) are selected as key parameters in characteristics of gas/liquid coaxial sprays from the dimensional analysis. The properties of shear coaxial sprays are compared with those of swirl coaxial sprays through the macroscopic and microscopic analysis. Macroscopic similarities between shear and swirl coaxial sprays are revealed under flow conditions of high momentum flux ratio. Also, empirical correlations between the mean drop diameters(D32) and operating conditions of coaxial sprays are proposed in this paper.

키워드

참고문헌

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