DYNAMIC RESPONSE OF FLOATING WIND TURBINE UNDER CONSIDERATION OF DYNAMIC BEHAVIOR OF CATENARY MOORING-LINES

• Main Authors: Guo SX(郭双喜), Li YL, Li M(李敏), Chen WM(陈伟民), Fu YQ, Chen, WM (reprint author), Chinese Acad Sci, Key Lab Mech Fluid Solid Coupling Syst, Inst Mech, Beijing 100190, Peoples R China.
• Format: Other/Unknown Material
• Language: English
• Published: AMER SOC MECHANICAL ENGINEERS 2017
• Subjects: Model Test; Spar; Systems; Dynamic Response; Floating Wind Turbine; Catenary Mooring-line; Dynamic Tension; Arctic
• Online Access: http://dspace.imech.ac.cn/handle/311007/72176

Recently, wind turbine has been developed from onshore area to offshore area because of more powerful available wind energy in ocean area and more distant and less harmful noise coming from turbine. As it is approaching toward deeper water depth, the dynamic response of the large floating wind turbine experiencing various environmental loads becomes more challenge. For examples, as the structural size gets larger, the dynamic interaction between the flexible bodies such as blades, tower and catenary mooring-lines become more profound, and the dynamic behaviors such as structural inertia and hydrodynamic force of the mooring-line get more obvious. In this paper; the dynamic response of a 5MW floating wind turbine undergoing dfflerent ocean waves is examined by our FEM approach in which the dynamic behaviors of the catenary mooring-line are involved and the integrated system including flexible multi-bodies such as blades, tower, spar platform and catenaries can be considered. Firstly, the nonlinear dynamic model of the integrated wind turbine is developed. Different from the traditional static restoring force, the dynamic restoring force is analyzed based on our 3d curved flexible beam approach where the structural curvature changes with its spatial position and the time in terms of vector equations. And, the modified finite element simulation is used to model a flexible and moving catenary of which the hydrodynamic load depending on the mooring-line's motion is considered Then, the nonlinear dynamic governing equations is numerically solved by using Newmark-Beta method. Based on our numerical simulations, the influences of the dynamic behaviors of the catenary mooring-line on its restoring performance are presented. The dynamic responses of the floating wind turbine, e.g. the displacement of the spar and top tower and the dynamic tension of the catenary, undergoing various ocean waves, are examined. The dynamic coupling between different spar motions, i.e. surge and pitch, are discussed too. Our numerical results ...