Research On Large Wind Turbine Blade Lay-up Design And Finite Element Numerical Simulation

The length and weight of the blade increase as wind turbine unit capacity increases, which brings great challenges for structural design of the wind turbine blade. The study on wind turbine blade structure layer design is of important significance to improve safety and reliability of the blade.Firstly, lay-up design method of the composite wind turbine blade structure is studied in the paper. According to empirical formula put forward by the National Renewable Energy Laboratory, it researched lay-up design method of the skin and root of the blade. Then lay-up design of the spar cap is proceeded by MATLAB procedure which is based on composite classical laminate theory and Newton Iteration Method. For the trailing edge panels and webs, stiffess analysis method of sandwich plate combined with Newton Iteration Method are used to determine its lay-up to satisfy the buckling strength requirement. According to the methods proposed above, lay-up thickness of the skin, spar caps, trailing edge, shear webs and root of1.5MW wind turbine blade is solved.Secondly, finite element modeling method of the composite wind turbine blade is reseached in the paper. Based on1.5MW wind turbine blade model, methods of space coordinate solving, three-dimensional modeling, geometrical model importing,finite element mesh generation, boundary conditions applying as well as lay-up designing are discussed in detail.Finally, based on1.5MW wind turbine blade model, it analysised stress characteristics of the different regions of the blade by means of finite elements analysis software, including leading edge, spar cap, webs and trailing edge, meanwhile check analysis is performed by using different strength criteria. The results show that:compared with Tsai-Hill criterion or Tsai-Wu criterion, for check analysis of double fiber cloth of leading edge, shear webs and trailing edge regions, Hoffman criterion is more safety. Compared with Hoffman criterion, for check analysis of double fiber cloth of the spar caps, Tsai-Hill criterion or Tsai-Wu criterion is more safety. Compared with Hoffman criterion and Tsai-Wu criterion, for check analysis of unidirectional fiber cloth of the spar caps, Tsai-Hill criterion is more safety.