This Thesis investigates the methods which are currently avail-able for the dynamic analysis of Offshore Mooring Terminals, particularregard being paid to Single Point Mooring (SPM) Terminals. Variousaspects of the problem are considered in turn, these being the randomvibration of non-linear systems, the analysis of catenary mooringlines, buoy dynamics, ship motions, second order (or slow drift)forces and motions, and low frequency motions caused by instabilities.These various aspects are then applied to the dynamic analysis of aSingle Buoy Storage (SBS) System and the effect of the method ofanalysis employed, the system dimensions and the environmentalconditions on the computed response is investigated.A Time Domain investigation of the stability of the SBS Systemin the presence of wind and current alone reveals that the system isonly unstable for combinations of wind and current which are unlikelyto occur in practise. A static offset position is then assumed andthe calculation of the three-dimensional first and second orderresponse to random waves is performed in the Frequency Domain, linearwave theory being used. The first order wave forces are calculated byusing strip theory for the tanker and Morison's equation for the buoy.The second order response in surge, sway and yaw is calculated by areflection coefficient method, these coefficients being obtained frompublished literature. The non-linear mooring system and the dragforces acting on the buoy are linearised using the equivalentlinearisation method, due account being taken of the coupling betweenthe first and second order response. The model developed for the firstorder response of the system allows the use of a spreading functionin the incident wave spectrum.The accuracy of linearisation techniques and the statistics ofthe second order force and response are also investigated.
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