DOI QR코드

DOI QR Code

Comparison of Potential and Viscous Codes for Water Entry Problem

  • Received : 2011.12.15
  • Accepted : 2012.02.06
  • Published : 2012.02.29

Abstract

This paper presents a comparison of potential and viscous computational codes for the water entry problem. A po-tential code was developed which adopted the boundary element method to solve the problem. A nonlinear free surface boundary condition was integrated to find new locations of free surface. The dynamic boundary condition was simplified by taking constant potential values for every time steps. The simplified dynamic boundary condition was applied in the new position of the free surface not at the mean level, which is the usual practice for linearized theory. The commercial code FLUENT was used to solve the water entry problem from the viscosity point of view. The movement of the air-liquid interface is traced by distribution of the volume fraction of water in a computational cell. The pressure coefficients were compared with each other, while experimental results published by other researchers were also examined. The characteristics of each method were discussed to clarify merits and limitations when they were applied to the water entry problems.

Keywords

References

  1. Armand. J.L, Cointe. R, Hydrodynamic impact analysis of a cylinder, Journal of Offshore Mechanics and Arctic Engineering ASME 9, (1987) 237-243.
  2. Dobrovol'skaya. Z.N, On some problems of similarity flow of fluid with a free surface, Journal of Fluid Mechanics 36(4), (1969) 805-829. https://doi.org/10.1017/S0022112069001996
  3. Chuang. S.L, Experiments on flat-bottom slamming, Journal of Ship Research, (1966) 10-17.
  4. B. Kim, Yung. S. Shin, 2003. An efficient numerical method for a solution of two-dimensional hydrodynamic impact problems, Proceedings of the 13th international offshore and polar engineering conference Honolulu Hawaii May, (2003) 25-30.
  5. Korobkin. A, 1996. Water impact problems in ship hydrodynamics, Advances in Marine Hydrodynamics (Editor: M. Okushu), (1996) 323-371.
  6. Mei. X, Liu. Y, Yue. D.K.P, on the water impact of general two-dimensional sections, Applied Ocean Research 21(99), 1-15.
  7. SNAME, Notes on Ship Slamming, Technical and Research Bulletin 2-30, The Society of Naval Architects and Marine Engineers.(1993)
  8. Von Karman, The impact on sea plane floats during landing, NACA Technical Note 321 (1929)
  9. Wagner, H, Uber stoss- und Gleitvergange an der Oberflache von Flussigkeiten, Z. Angew. Math. Mech, 12(4), (1932) 193-215. https://doi.org/10.1002/zamm.19320120402
  10. Watanabe. T, Analytical expression of hydrody-namic impact pressure by matched asymptotic expansion technique, Transactions of West-Japanese Society of Naval Architects 71, (1986) 77-85.
  11. Zhao. R, Faltinsen. O.M, Water entry problem of two-dimensional bodies, Journal of Fluid Mechanics 246, (1993) 593-612. https://doi.org/10.1017/S002211209300028X
  12. Zhao. R, Faltinsen. O.M, Aarsnes. J.V, Water entry of arbitrary two-dimensional sections with and without flow separation, Proceedings 21st (1996) 408-423.