Calculations of current-induced forces on moored tankers, using the theory of manoeuvring ships
- Agip S.p.A., Milan (Italy). Engineering Research and Development Dept.
The knowledge of current induced loads on moored tankers is important in the design of mooring lines. Normally, these current loads are determined from controlled laboratory experiments and field tests or from the Oil Companies International Marine Forum (OCIMF) data (1977). Chakrabarti (1995) mentions that the validity of some of this data is doubtful, and he conducted some tank tests. To save time involved in preparation of elaborate tank tests, it will be useful to have some analytical tools to calculate the current induced loads. In this paper, an attempt has been made to calculate the lateral forces in current only conditions, using the theory of manoeuvring ships. The manoeuvring model was developed by Wellicome (1981). The sway forces on the hull are modelled by conformal transformation of the hull into a circle plane and applying the flow field. The forces on the bilge keel are modelled by vortex panel method. The results for the simulation are compared with the test results of Chakrabarti (1995). There is good correlation between the experimental and theoretical results for the case of hull with bilge keels. This is true for the streaming flow velocity up to an angle of 45 to the longitudinal direction of the hull. For the case of bare hull, the computational model grossly underpredicts the sway forces. This may be due to the dominance of viscous forces than the potential ones.
- OSTI ID:
- 449674
- Report Number(s):
- CONF-9606279-; ISBN 0-7918-1490-4; TRN: IM9714%%231
- Resource Relation:
- Conference: 14. international conference on offshore mechanics arctic engineering (OMAE), Florence (Italy), 16-20 Jun 1996; Other Information: PBD: 1996; Related Information: Is Part Of Proceedings of the 15. international conference on offshore mechanics and arctic engineering -- OMAE 1996. Volume 1, Part A: Offshore technology; Chakrabarti, S.K. [ed.] [Chicago Bridge and Iron Technical Services Co., Plainfield, IL (United States)]; Pontes, M.T. [ed.] [Inst. Nacional de Engenharia e Tecnologia Industrial, Lisbon (Portugal)]; Maeda, Hisaaki [ed.] [Univ. of Tokyo (Japan)]; Falzarano, J. [ed.] [Univ. of New Orleans, LA (United States)]; Schofield, P. [ed.] [W.S. Atkins, Surrey (United Kingdom)]; Morrison, D. [ed.] [Shell E and P Technology Co., Houston, TX (United States)]; PB: 530 p.
- Country of Publication:
- United States
- Language:
- English
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