On the evaluation of diffraction forces on a floating semisubmersible unit
Abstract
The importance of the accurate evaluation of diffraction forces on offshore structures is of paramount importance in the determination of response amplitude operators of motions as well as of the accelerations in several points of interest which are directly linked to the comfort onboard and operational indexes. It is well known that the higher the sea state to operate the better the efficiency and operability characteristics of the floating structures.
The purpose of the present paper is to show the significant differences between the evaluations carried out when Froude - Kryloff hypothesis is used and the results when the influence of structure geometry is considered. The calculations have been carried out for the ITTC semisubmersible, SR 192, using a 3D computer code based on Green functions method.
Dedicated to our Prof. Dr. Eng. Liviu Dan Stoicescu, member of the Romanian Academy of Technical Sciences, on the occasion of his 85th birthday.
Downloads
References
[2]. Faltinsen, O.M., Michelsen, F.C., “Motions of Large Structures in Waves at Zero Froude Number”, Proceedings of the International Symposium on the Dynamics of Marine Vehicles and Structures in Waves, University College of London, UK, pp. 91-106, 1974.
[3]. Faltinsen, O.M., “Sea Loads on Ship and Offshore Structures”, Cambridge University Press, Cambridge, 1993.
[4]. Hooft, J.P., “A Mathematical Method of determining Hydro-dynamically Induced Forces on a Semisubmersible”, SNAME Annual Meeting, New York, USA, November 1971.
[5]. Van Oortmerssen, G., The Motions of a Moored Ship in Waves, NSMB, Publication No.510, Wageningen
[6]. Takagi, M., Arai, S.I., Takezava, S., Tanaka, K., Takarada, N., „A Comparison of Methods for Calculating the Motion of a Semisubmersible”, Ocean Engineering, vol. 12, no. 1, pp. 45-97, 1985.
[7]. Paulling, J.R., „Hydrodynamic Synthesis of Marine Structures”, Theoretical and Applied Mechanics, IUTAM, Elsevier Science Publishers B.V., 1985.
[8]. Pinkster, J.A., van Oortmerssen, G., “Computation of the first and second order wave forces on oscillating bodies in regular waves”, Second International Conference on Numerical Ship Hydrodynamics, University of California, Berkeley, September 1977.
