Journal of the Society of Naval Architects of Korea (대한조선학회논문집)

The Society of Naval Architects of Korea (대한조선학회)
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A Study on BEM-Based Numerical Simulation Technique for Underwater Explosions

수중 폭발 시뮬레이션을 위한 경계 요소법 기반의 수치 해석 기법 연구

  • Choung, Joonmo (Dept. of Naval Architecture & Ocean Engineering, Inha University) ;
  • Lee, Jae-bin (Dept. of Naval Architecture & Ocean Engineering, Inha University)
  • 정준모 (인하대학교 조선해양공학과) ;
  • 이재빈 (인하대학교 조선해양공학과)
  • Received : 2020.02.11
  • Accepted : 2020.06.05
  • Published : 2020.10.20
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Abstract

Recoverability and vulnerability of navy ships under underwater explosion are critical verification factors in the acquisition phase of navy ships. This paper aims to establish numerical analysis techniques for the underwater explosion of navy ships. Doubly Asymptotic Approach (DAA) Equation of Motion (EOM) of primary shock wave and secondary bubble pulse proposed by Geers-Hunter was introduced. Assuming a non-compressive fluid, reference solution of the DAA EOM of Geers-Hunter using Runge-Kutta method was derived for the secondary bubble pulse phase with an assumed charge conditions. Convergence analyses to determine fluid element size were performed, suggesting that the minimum fluid element size for underwater explosion analysis was 0.1 m. The spherical and cylindrical fluid domains were found to be appropriate for the underwater explosion analyses from the fluid domain shape study. Because the element size of 0.1 m was too small to be applied to the actual navy ships, a very slender beam with the square solid section was selected for the study of fluid domain existence effect. The two underwater explosion models with/without fluid domain provided very similar results in terms of the displacement and stress processes.

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References

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