Structure Analysis Of Support Structure For Jacket Offshore Wind Turbine

Wind energy is a renewable clean energy, which has its superiority. With the large-scale development and utilization of offshore wind energy, offshore wind turbine has become another kind important ocean engineering structures. In this thesis, based on a 3 MW support structure for the four leg jacket offshore wind turbine, considering the complex ocean environment load and soil effect and using the finite element software SACS, the static, dynamic and fatigue characteristics of the support structure for offshore wind turbine are studied. The main works are as follows:(1) A detailed study of the complex marine environment and its related theory of the offshore wind turbine foundation, including the calculation of aerodynamic load, the choice of wave theory, and the calculation of wave load and current load.(2) Combined with the given the size and related rules, the initial support structure model of offshore wind turbine was established, using the finite element software SACS. The pile soil interaction below mud was simulated with PSI module. The control case and coefficient were determined based on the marine environment load of structure.(3) According to the results of static calculation, checked the member stress, joint punching and shearing stress and the bearing capacity of pile foundation. By the value of UC in the calculation results, determining whether the structure compliance with the specification requirements, and finding out the most dangerous joint and its corresponding case.(4) Considering the probability distribution of wave direction, fatigue loads are applied to the support structure according to the actual situation. Based on the fatigue analysis theory, analyzed the wave spectrum fatigue damage of the structure under the omnidirectional wave load, and calculated the fatigue damage and fatigue life of the main point of the structure. A more accurate and reasonable method of fatigue analysis is provided to study the structure of offshore wind turbine. Based on the results above, the structure is optimized to analyze the impact of leg wall thickness on each node's structure fatigue strength.