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Numerical Study about Behavior of an Ejecting Projectile for Varying Initial Conditions

초기 조건 변화에 따른 사출 운동체의 거동에 관한 수치적 연구

  • Jo, Sung Min (Korea Advanced Institute of Science and Technology) ;
  • Kwon, Oh Joon (Korea Advanced Institute of Science and Technology)
  • Received : 2019.08.19
  • Accepted : 2019.10.16
  • Published : 2019.11.01

Abstract

In the present study, analyses of initial behavior of an air-launched projectile for varying initial conditions are performed by coupling computational fluid dynamics and 6 degrees of freedom calculations. Accuracy of the present numerical methods is validated by comparing the present result with the measured data. Launching safety analyses are carried out for various ejecting conditions by considering weight of the projectile and magnitude of front and rear ejector forces as the major parameters of initial behavior of the projectile. A response surface of the projectile launching safety is obtained in the range of the major parameters. In all the conditions of zero rear ejector force, unsafe launching behavior is observed. As the weight of the projectile decreases, the initial launching behavior becomes more unsafe.

본 연구에서는 전산유체역학과 6자유도 운동 해석을 결합하여 사출 조건 변화에 따른 공중 발사 운동체의 초기 거동에 관한 해석이 수행되었다. 해석 결과를 실험 측정 데이터와 비교함으로써 해석 기법의 정확성을 검증하였다. 다양한 사출 조건에 대한 사출 안정성 해석이 수행되었으며, 사출 운동체의 초기 거동에 지배적인 영향을 미치는 주요 인자로써 운동체의 무게, 전방 및 후방 사출력의 크기를 고려하였다. 이들 인자의 변화 범위에 대한 운동체의 사출 안정성 반응 곡면이 도출되었다. 모든 조건에서 후방 사출력이 작용하지 않는 경우에는 운동체의 안정 사출이 불가한 것으로 나타났다. 또한 운동체의 무게가 감소될수록 불안정 사출 영역이 확대되었다.

Keywords

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