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

The Korean Society for Aeronautical and Space Sciences (한국항공우주학회)
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The Study on the Fragment Ejection Velocity and Spray Angle from a High Explosive Cylindrical Warhead

실린더형 HE 탄두 폭발 시 파편의 속도 및 발사각 추정방법 연구

  • Hwang, Changsu (Department of Aeronautical Science, Jungwon University) ;
  • Park, Younghyun (Department of Aeronautical Science, Jungwon University) ;
  • Park, Seikwon (Department of Aeronautical Science, Jungwon University) ;
  • Jung, Daehan (Department of Mechanical Engineering, Korea Air Force Academy) ;
  • Lee, Moonsik (Department of Natural Sciences, Korea Air Force Academy) ;
  • Kang, Sunbu (Department of Natural Sciences, Korea Air Force Academy) ;
  • Kim, Deuksu (Department of Natural Sciences, Korea Air Force Academy)
  • Received : 2019.08.02
  • Accepted : 2019.11.07
  • Published : 2019.12.01
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Abstract

We have studied the numerical analysis about the fragment ejection velocity and spray angle when the High Explosive warhead detonated at proximity distance at an aircraft. To study the physical quantities about the warhead components is very important to assessment the vulnerability of aircraft. Generally, the physical quantities about the components of a warhead such as the mass, length, diameter and charge to mass ratio are unknown. Therefore, it is required to estimate the physical quantities by using physical continuities of similar threats. The empirical formulas to understand the dependence among charge to mass ratio, length and diameter ratio were driven by using the physical parameters of similar threatening such as terrier, sparrow. As a result, we confirmed that the dead mass ratio was closed to 20% of warhead mass since the metal case of the proximity threat acts as a simple carrier. This implies that the effective length and diameter of High Explosive Compound is smaller than the length and diameter of warhead, and become a key to understand the large ejection gradient velocity and small spray angle of fragments within 6 degree.

본 연구는 항공기에 근접하여 폭발하는 고폭형 위협 무기의 파편 발사속도 및 발사각을 수치 해석적으로 추정한 결과이다. 고폭형 위협 무기에 대한 항공기의 취약성을 평가하기 위하여 탄두 구성품의 물리량을 이해하는 것은 매우 중요하다. 일반적으로 고폭형 위협 무기에 대한 구성품의 질량, 길이 및 직경 등 물리적 변수는 알려져 있지 않다. Terrier, Sparrow 등 유사 위협 무기들의 데이터를 이용하여 charge to mass 비율, 길이와 직경 비율 등과 관련된 경험식을 수치 해석적으로 유도하였다. 근접신관에 의하여 외부에 폭발하는 탄두에서 탄두 덮개 구성비는 20% 수준으로 나타났으며, 고폭 화약의 양쪽 끝부분에서 방사되는 파편의 발사속도 구배 현상이 뚜렷이 나타났지만 법선 방향에 대한 발사각은 6° 이내로 나타났다.

Keywords

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