Composite Overlapping Meshes for the Solution of Radiation Forces on Submerged-Plate

  • Kong, Gil-Young (Department of Ship Operating Systems Engineering, Korea Maritime University) ;
  • Lee, Sang-Min (Department of Ship Operating Systems Engineering, Korea Maritime University) ;
  • Lee, Yun-Sok (Department of Ship Operating Systems Engineering, Korea Maritime University)
  • 발행 : 2004.07.01

초록

The purpose of this study is to predict and understand the hydrodynamic forces and their nonlinear behaviors of fluid motion around the submerged plate oscillating near a free surface. To achieve this objective, we have developed a composite grid method for the solution of a radiation problem. The domain is divided into two different grids; one is a moving grid system and the other is a fixed grid system. The moving grid is employed for the body fitted coordinate system and moves with the body. This numerical method is applied to calculation of radiation forces generated by the submerged plate oscillating near a free surface. In order to investigate the characteristics of the radiation forces, the forced heaving tests have been performed with several amplitudes and different submergences near a free surface. These experimental results are compared with the numerical ones obtained by the present method and a linear potential theory. As a result, we can confirm the accuracy of the present method. Finally, the effect of nonlinear and viscous damping has been evaluated on the hydrodynamic forces acting on the submerged plate.

키워드

참고문헌

  1. Chung, J. S., 1977, 'Forces on Submerged Cylinders Oscillating near a Free Surface,' Journal of Hydronautics, Vol. 11, No. 3, pp. 100-106 https://doi.org/10.2514/3.63081
  2. Demirdzic, I. and Peric, M., 1990, 'Finite Volume Method for Prediction of Fluid Flow in Arbitrarily Shaped Domains with Moving Boundaries,' International Journal of Numerical Methods in Fluids, Vol. 10, pp. 771-790 https://doi.org/10.1002/fld.1650100705
  3. Fujikubo, M., Takaki, M., Xiao, T. Y. and Yanagihara, D., 2002, 'Structural Response and Strength of A New Type VLFS Using Submerged Plates,' Proceedings of 12th ISOPE, Kitakyushu, pp. 414-421
  4. Hinatsu, M. and Ferziger, J. H., 1991, 'Numerical Computation of Unsteady Incompressible Flow in Complex Geometry Using a Composite Multigrid Technique,' International Journal for Numerical Methods in Fluids, Vol. 13, pp. 971-997 https://doi.org/10.1002/fld.1650130804
  5. Lee, Y. G. and Miyata, H., 1990, 'A Finite-Difference Simulation Method for 2D Flows about Bodies of Arbitrary Configuration,' Journal of Society of Naval Architects of Japan, Vol. 167, pp. 1-8
  6. Lighthill, J., 1986, 'Fundamentals Concerning Wave Loading on Offshore Structures,' Journal of Fluid Mechanics, Vol. 173 https://doi.org/10.1017/S0022112086001313
  7. Park, J. C., Uno, Y., Matsuo, H., Sato, T. and Miyata, H., 2001 'Reproduction of Fully-Nonlinear Multi-Directional Waves By a 3D Viscous Numerical Wave Tank,' Proceedings of 11th ISOPE, Stavanger
  8. Takaki, M., Fujikubo, M., Higo, Y., Hamada, K., Kobayashi, M., Nakagawa, H., Morishima, S., Ando, K.and Tanigami, A., 2001, 'A New Type VLFS Using Submerged Plates:SUB-PLATE VLFS-Part 1 Basic Concept of System-,' Proceedings of 20th OMAE, Rio de Janeiro, OMAE-01-5017
  9. Takaki, M., Imai, Y., Lee, S. M., Shibata, S. and Chiba, S., 2002, 'Effect of a Submeerged-Plate on Hydrodynamic Forces Acting on a Very Large Floating Structure,' Transactions of West-Japan Society of Naval Architects, No. 103, pp. 195-204