Journal of Ship and Ocean Technology

The Society of Naval Architects of Korea (대한조선학회)
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A 3-Dimentional Radiation Diffraction Problem Analysis by B-Spline Higher-Order Panel Method

  • Kim Gun-Do (Maritime and Ocean Engineering Research Institute(MOERI), KORDI) ;
  • Lee Chang-Sup (Department of Naval Architecture and Ocean Engineering, Chungnam National University)
  • Published : 2006.03.01
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Abstract

The radiation problem for oscillating bodies on the free surface has been formulated by the over-determined Green integral equation, where the boundary condition on the free surface is satisfied by adopting the Kelvin-type Green function and the irregular frequencies are removed by placing additional control points on the free surface surrounded by the body. The B-Spline based higher order panel method is then applied to solve the problem numerically. Because both the body geometry and the potential on the body surface are represented by the B-Splines, that is in polynomials of space parameters, the unknown potential can be determined accurately to the order desired above the constant value. In addition, the potential expressed in B-Spline can be differentiated analytically to get the velocity on the surface without introducing any numerical error. Sample computations are performed for a semispherical body and a rectangular box floating on the free surface for six-degrees of freedom motions. The added mass and damping coefficients are compared with those by the already-validated constant panel method of the same formulation showing strikingly good agreements.

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References

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