Journal of the Korea Academia-Industrial cooperation Society (한국산학기술학회논문지)

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Numerical Experimentations on Flow Impact Phenomena for 2-D Wedge Entry Problem

2차원 쐐기형 구조물 입수 시 발생하는 유체 충격 현상에 대한 수치 실험적 연구

  • Yum, Duek-Joon (Department of Naval Architecture, Kunsan National University) ;
  • Du, Hun (School of Mechanical & Automative Engineering, Kunsan National University) ;
  • Kim, Young-Chul (School of Mechanical & Automative Engineering, Kunsan National University)
  • 염덕준 (군산대학교 조선공학과) ;
  • 두훈 (군산대학교 기계자동차공학부) ;
  • 김영철 (군산대학교 기계자동차공학부)
  • Received : 2011.05.30
  • Accepted : 2011.08.11
  • Published : 2011.08.31
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Abstract

In this study, numerical analyses for slamming impact phenomena have been carried out using a 2-dimensional wedge shaped structure having finite deadrise angles. Fluid is assumed incompressible and entry speed of the structure is kept constant. Geo-reconstruct(or PLIC-VOF) scheme is used for the tracking of the deforming free surface. Numerical analyses are carried out for the deadrise angles of $10^{\circ}$, $20^{\circ}$ and $30^{\circ}$. For each deadrise angle, variations are made for the grid size on the wedge bottom and for the entry speed. The magnitude and the location of impact pressure and the total drag force, which is the summation of pressure distributed at the bottom of the structure, are analyzed. Results of the analyses are compared with the results of the Dobrovol'skaya similarity solutions, the asymptotic solution based on the Wagner method and the solution of Boundary Element Method(BEM).

본 연구는 유한한 크기의 선저경사각을 갖는 2차원 쐐기형 구조물의 슬래밍 충격 현상을 수치 해석하였다. 비압축성 유체를 가정하였으며, 구조물의 입수 속도는 일정하게 유지하였다. 자유수면의 대 변형 및 동적 거동의 해석을 위해서 Geo-reconstruct(or PLIC-VOF) scheme을 사용하였다. 선저경사각이 $10^{\circ}$, $20^{\circ}$ 및 $30^{\circ}$인 경우에 대해서 해석을 수행하였으며, 각각의 선저경사각에 대하여 입수면의 격자 크기 및 입수 속도를 변화시켜 슬래밍 충격력 수치 해석 결과에 미치는 영향을 조사하였다. 수치해석 결과는 Dobrovol'skaya(1969)의 상사해(similarity solution), Wagner 방법에 기초한 점근해(asymptotic solution) 및 경계요소법(Zhao et al.(1993))에 의한 해석 결과와 비교하였다.

Keywords

References

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