Structural Strength Analysis And Optimization Design Of Large-scale Wind Turbine Hub

Wind turbine hub is a complicated key part that connects the blades and the shaft, and it bears the extremely complex loads condition. So it is essential to ensure the strength and life requirement of the hub, as well as the light weight demand.This paper conducted the strength analysis and structure optimization design of a 2MW wind turbine hub under the support of the technological innovation major special projects "A 5MW or Bigger-scale Wind Turbine Supporting Bearings". Finite element method is adopted to complete the strength analysis and verification, and topological optimization method is applied to conduct the conceptual model of the original hub structure. New structure design of the hub whose wall thickness is optimal is obtained based on the dimension optimization by response surface method, and is compared with original structure by performance analysis. The main job and research description are as follows:(1) Static strength and fatigue life analysis and verification of the original wind turbine hub structure were completed based on finite element method. Finite element model of the whole structure which considered the boundary condition equivalent model is built. The final static strength verification result demonstrated that the wind turbine hub structure optimization can be operated under the condition that the wind turbine hub structure satisfies the strength limit request and the wind turbine hub has the requested optimization space.(2) The concept model design scheme of wind turbine hub structure was obtained based on the topological optimization design of Optistruct platform by using two different optimization methods. Based on the equivalent model of the boundary condition, topological optimization model is built. According to two different optimization schemes, the concept model design scheme of wind turbine hub structure was obtained based on the density contours of the topological result.(3) The dimension optimization design and performance analysis of wind turbine hub were accomplished based on the method of response surface. The multi-objective optimization scheme was established based on the hub structure parameter to obtain the new structure model. The new scheme performance analysis of wind turbine hub and the performance comparison with the original one were conducted after the optimal design scheme of wind turbine hub was obtained.The result showed that the new structure of the hub meet the extremely strength and fatigue life requirements, the fatigue life of the hub was 29 years, and the weight of the hub was reduced by 9.5%, which stated that the target of lightweight was accomplished, and hub material is fully used. The new wind turbine hub structure model can be verified in the engineering practice.