Research On Ship Impact Performance Of Floating Wind Turbine Structure

Clean energy accounts for a growing proportion of human energy.Traditional onshore wind power is unable to meet the demand of human electricity.However,most of the Marine wind resources are distributed in the deep-sea area with the water depth of more than 60 meters,where the fixed foundation of these sea areas cannot be applied.In this way,the study of floating wind turbine at sea has become the top priority of offshore wind power research.With the continuous deployment of floating wind farms in the world,the collision of far-sailing ships and service ships with floating wind farms occurs from time to time.This will not only affect the daily operation of the wind farms in the sea,but also cause the bad consequences of the collapse of the wind turbine.Therefore,it's important to carry the research on the performance and dynamic response of the floating tension leg wind turbine,when it encounters the collision of different types of ships,and design an economical and reliable anti-collision structure.They are of great theoretical significance and practical application value for the safety performance of offshore floating wind turbine structure,and conducive to the efficient operation of offshore wind farm.This paper is based on the actual structure of TLP floating wind turbines and offshore service ships,and it uses the ALE method.With the LS-DYNA finite element simulation software,this paper establishes the fluid-solid coupling calculation model of the collision between the two.At the same time,the model was established using the same method aiming at the single pile foundation fan collision.Comparing with the calculation results of the model established by the additional water quality method,the accuracy of the fluid-solid coupling model established by the ALE method was verified.Using the TLP floating wind turbine collision model,this paper analyzes the changes of the kinetic energy and internal energy of the system,the impact of the mass,speed,collision deviation distance,and collision location on the collision force of the ship.Meanwhile,the six commonly used collision force specification formulas were analyzed and compared,as well as the elastoplastic deformation of the wind turbine foundation and the acceleration response of the nacelle on the top of the turbine.The results show that in the case of the same initial kinetic energy of the ship,the higher the collision deviation distance,the smaller the collision force;the collision force caused by the side collision is significantly higher tha n the positive collision.For the calculation of the collision conditions of TLP floating wind turbine,the “General Code for the Design of Highway Bridges and Culverts” and the Eurocode code formula are the most accurate.The higher the initial propagation kinetic energy,the greater the peak of the elastoplastic strain and cabin acceleration time history curve caused by the collision.According to the collision simulation results of TLP floating wind turbine,six different structures of anti-collision facilities were designed,and their finite element analysis models were established.Based on the collision force and energy change curve during the collision process,the principle of anti-collision facilities protection was analyzed.The result shows that the independent cylinder is the best structure.Then,it was further optimized according to three factors of the anti-collision facility of the independent cylinder–size,thickness,and material.The best plan for the anti-collision facility of the independent cylinder was 4 m in diameter,5 mm in wall thickness,and using Q195 steel.Using the best anti-collision facilities,the protection performance was verified under the riskiest side-impact conditions,which proved that it can play a right protective role under all conditions.