Feature of Spray Transport and Atomization from Two-Phase Swirling Jet with Air-to-Liquid Mass Ratio

공기액체질량비에 따른 이류체 선회형 분사의 분무거동 및 미립화 특성

  • Lee, Sam-Goo (Dept.of Mechanical Aerospace System Engineering, Chonbuk National University)
  • Published : 2004.06.01

Abstract

Experiments were performed in a two-phase swirling spray facility that has been described elsewhere. Measurements of spray transport and drop size distribution are analyzed over wide ranges of air to liquid mass flow ratios, utilizing four different internal mixing pneumatic nozzles. The spatial distributions of mean velocities. fluctuating velocities, and velocity-diameter correlation were quantitatively analyzed. Also, the exponential correlation curves were obtained with ALR along the spray centerline, which indicated an approximately identical formulation regardless of ALR. It indicated that the atomization characteristics were remarkably superior in the case of 30o of swirl angle with higher ALR. Among other things. nozzle configuration is one of the significant parameters affecting spray phenomena from an internal mixing nozzle. Turbulence intensities are increasingly degenerated with an increase of nozzle configuration, allowing a rapid increment of drop size distribution.

선회형 미립화기의 분무거동에 관한 논의는 현재 여러 연구자들에 의해 활발히 논의되고 있다. 본 연구에서는 이류체 내부혼합형 선회노즐의 특성을 파악하고자 공기와 액체의 질량 비를 바꿔가며 최적의 미립화 조건을 알아보기 위하여 실시되었다. 이를 위하여 분무 유동장의 평균속도, 파동속도 및 액적크기에 관한 비교를 정량적으로 분석하였다. 각 유동조건에 따른 지수함수를 만족하는 상관관계 또한 도출하였는데, 이는 질량 비에 관계없이 거의 동일함을 알 수 있었고, 질량비가 높을수록 선회 각이 30o인 경우가 미립화 특성이 가장 우수하였다. 따라서, 본 연구에서 이루어진 결과에서는 노즐의 형상이 분무유동에 미치는 여러 인자 중 가장 중요한 것이라 여겨진다.

Keywords

References

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