Journal of the Korean Society for Aeronautical & Space Sciences (한국항공우주학회지)

The Korean Society for Aeronautical and Space Sciences (한국항공우주학회)
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Effects of Convective Velocity and Ambient Pressure on the Characteristics of Heptane Droplet Vaporization in Supercritical Environments

초임계상태에서 주위 유동 속도와 압력 변화에 따른 헵탄 액적의 기화 특성

  • 임종혁 (한국항공대학교 항공우주 및 기계공학과) ;
  • 이봉수 (한국항공대학교 항공우주 및 기계공학과) ;
  • 구자예 (한국항공대학교 항공우주 및 기계공학부)
  • Published : 2005.04.01
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Abstract

The vaporization characteristics of a liquid heptane droplet in a supercritical nitrogen flow is numerically analyzed. The present model can account for real gas effects, liquid-phase internal circulation, variable thermodynamic properties and high-pressure effects. Time marching method with preconditioning scheme is employed to handle the low Mach number flows in dense heptane droplet region. Computations are made for the wide range of convective velocity and ambient pressure. Numerical results indicate that the droplet deformation becomes stronger by increasing the Reynolds number and it becomes relatively weak by increasing the pressure.

초임계 상태의 질소 유동 환경에서 헵탄 액적의 기화 특성을 수치적으로 연구하였다. 더불어 실기체 효과와 액적 내부 순환, 다양한 열역학적 물성치 및 고압 효과를 고려하였다. 또한 헵탄 액적 바로 근처에서의 저속 유동 문제를 풀기 위하여 예조건화 스킴을 적용한 시간 전진법을 수치 코드에 적용하였다. 주위 유동 속도와 주위 압력을 변화 시켜가면서 액적의 거동을 살펴보았다. 유동 속도 증가로 인한 레이놀즈수의 증가에 따라 액적의 변형이 활발히 이루어졌고, 동일한 레이놀즈수에 대해서는 압력이 높아질수록 액적의 변형이 약화되었다.

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References

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