Free Vibration Experimental Study Of Hydrodynamic Characteristic Of Heave Plates On The SPAR Platform

With development of ocean oil resource exploitation in deep ocean, all kinds of oil production platform come forward frequently, which fit in with deep ocean environment. Because of good motion characteristic and cheap construction cost of Spar Platform, more scholars of ocean engineering will pay attention to it. Heave plate as an important part of Spar Platform, which was installed at bottom of body of platform, can offer extra hydrodynamic force damping and improve added mass and decrease heave motion of platform. Spar platform obtain large motion added mass; at the same time of satisfy requirement of platform motion function, decrease draught, extend heaving period, decreasing construction cost of platform by a large margin, improving economical efficiency conspicuously.In this page, the free decay of single and multi heave plate of Spar platform model test was studied under different initial status comprehensively and systematically. It contains different thickness single heave plate and different space of multi heave platform was studied by the free decay experiment in the deep ocean spar platform, under function of different initial displacement, different the spring tension, and single heave plate under different submerged depth, was studied by free decay experiment also.This page accords to the Morison formula, we get Time Displacement process from this experiment, then using it to obtain velocity and acceleration of free vibration; then using Least-square method, analysing viscous damping coefficient and added mass coefficient of heave plate in different initial status conditions, also analysing the changes of viscous coefficient and added mass coefficient, in the change of initial status, and comparing with hydrodynamic performance getting from Single and Multi plates under same initial status; discovering the relation of viscous damping force and velocity of movement in process of heaving plate vibration, offering reference frame in designing of heave plate platform and calculation and safety performance evaluation respect.