• 제목/요약/키워드: HLL 리만 솔버

검색결과 2건 처리시간 0.017초

저감속 회수장비 시험조건에 따른 초음속 시험탄 감속특성에 대한 수치해석적 연구 (Numerical Studies on the Deceleration Characteristics of Supersonic Projectile According to the Test Condition Parameters in a Soft Recovery System)

  • 송민섭;김재훈
    • 한국군사과학기술학회지
    • /
    • 제23권5호
    • /
    • pp.485-493
    • /
    • 2020
  • Numerical analyses were performed using a one-dimensional Euler equation and Godunov Harten-Lax-Van Leer(HLL) Riemann solver in order to study the deceleration characteristics of a 155 mm projectile in a soft recovery system. The soft recovery system consisting of a series of pressure tubes is a system that decelerates the test projectile fired at supersonic speed using a high-pressure gas and filled water inside. Therefore, depending on the gas pressure and the amount of water filling, the deceleration and the exit velocity of the test projectile inside the pressure tube are determined. In this paper, the deceleration characteristics of the test projectile were analyzed according to the gas pressure and water mass filled.

저감속 회수장비에서 초음속 시험탄 속도에 대한 이론적 및 실험적 비교 연구 (Analytical and Experimental Comparison of the Velocity of a Supersonic Projectile in the Soft Recovery System)

  • 송민섭;김재훈
    • 한국군사과학기술학회지
    • /
    • 제24권6호
    • /
    • pp.619-628
    • /
    • 2021
  • In order to compare numerical analyses made by Song and Kim needed for predicting gas and water filling with experimental results we conducted an experiment to recover a test projectile (43.7 kg with a 155 mm diameter) at a velocity of 775 m/s in a soft recovery system with a length of 179 m using pressurized gas and filled water. The soft recovery system consisting of a series of pressure tubes had a diaphragm, piston, and water plug for filling the pressurized gas and water. We installed a continuous wave Doppler radar system for velocity measurements of the test projectile travelling in the pressure tubes and pressure transducers for measuring the pressure in the soft recovery system. Continuous wave Doppler radar has the advantage of achieving real-time measurements of the velocity of a test projectile. The velocity-time curve of the test projectile, measured using the continuous wave Doppler radar, and the pressure profile were compared with the numerical analysis results. The experiment results show good agreement with the numerical analysis results based on the one-dimensional Euler equation with an HLL Riemann solver.