Numerical Modeling of a Spar Platform Tethered by a Mooring Cable

作     者：ZHU Xiangqian YOO Wan-Suk 

作者机构：Computer Aided Engineering Laboratory School of Mechanical Engineering Pusan National University 

出 版 物：《Chinese Journal of Mechanical Engineering》 (中国机械工程学报（英文版）)

年 卷 期：2015年第28卷第4期

页      面：785-792页

核心收录：

学科分类：081505[工学-港口、海岸及近海工程] 08[工学] 080203[工学-机械设计及理论] 0815[工学-水利工程] 0824[工学-船舶与海洋工程] 0802[工学-机械工程] 0814[工学-土木工程] 082401[工学-船舶与海洋结构物设计制造] 

基　　金：Supported by Human Resources Development Program of Korea Institute of Energy Technology Evaluation and Planning(KETEP) Ministry of Trade,Industry and Energy of Korea(Grant No.20134030200290) 

主　　题：numerical modeling dynamic simulation spar platform mooring cable spherical joint 

摘      要：Virtual simulation is an economical and efficient method in mechanical system design. Numerical modeling of a spar platform, tethered by a mooring cable with a spherical joint is developed for the dynamic simulation of the floating structure in ocean. The geometry modeling of the spar is created using finite element methods. The submerged part of the spar bears the buoyancy, hydrodynamic drag force, and effect of the added mass and Froude-Krylov force. Strip theory is used to sum up the forces acting on the elements. The geometry modeling of the cable is established based on the lumped-mass-and-spring modeling through which the cable is divided into 10 elements. A new element-fixed local frame is used, which is created by the element orientation vector and relative velocity of the fluid, to express the loads acting on the cable. The bottom of the cable is fixed on the seabed by spring forces, while the top of the cable is connected to the bottom of the spar platform by a modified spherical joint. This system suffers the propagating wave and current in the X-direction and the linear wave theory is applied for setting of the propagating wave. Based on the numerical modeling, the displacement-load relationships are analyzed, and the simulation results of the numerical modeling are compared with those by the commercial simulation code, Proteus DS. The comparison indicates that the numerical modeling of the spar platform tethered by a mooring cable is well developed, which provides an instruction for the optimization of a floating structure tethered by a mooring cable system.