| With the continuous increase of the power of the wind turbine,the size of the blade is becoming more and more,and a serious safety accident will occur if the design is unsuitable.How to ensure the safe and stable operation of the wind turbine has become one of the most important factors that the designers need to consider.From the view of the operating environment of the wind turbine,the blade has been in the high altitude environment with strong wind sand and pressure for a long time.In addition to requiring a material that is resistant to erosion,high strength,and light weight as the main production material for the blades,a reasonable structural design is required.For the design of the composite blade,the theoretical support,the simulation calculation and the experimental verification are indispensable,and the safety and reliability of the blade can be guaranteed.The blades are subjected to various types of loads such as tension,compression,bending,and torsion during operation.Analysis of the effects of the blades on the blades themselves is of great significance.This article mainly studies the bending of the blades.This paper takes the 8MW wind turbine blade as the object,based on the momentum principle of leaf element,uses the NH02 series airfoil to carry out preliminary aerodynamic shape design,and translates the parameters obtained from the design into actual space coordinates.The 3D solid modeling of the blade is performed using Auto CAD and UG software.According to the lamination theory,the glass fiber reinforced composites were subjected to bending tests.The analysis showed that the bending strength of the glass fiber reinforced resin-based laminates was mainly provided by the 0° ply.Adding a certain percentage of ±45° plies can slightly increase the bending strength.In the form of fractures,laminates with ±45°plies have significant advantages when the material is fractured,and laminates with single direction fibers are prone to complete fracture,and the addition of ±45° plies can prevent this from happening.The suction surface,pressure surface and web molds were created based on the blade solid model,and were made in 3D printing.The beam caps,webs,and skins are laid out in layers to determine their configuration and dimensions,and they are laid on the resulting molds and finally the blade models are obtained.Through the static load test of the blade model,the tip displacement and the strain data of the spar cap are obtained.It can be seen that the carbon fiber has a significantly better performance than the glass fiber,and the spar cap or web is changed to a mixed layer,which is better than the single layer in the anti-flapping.Among them,the 0° ply angle is better than the ±45°ply angle forimproving the anti-flare resistance of the blade.Replacement of the ±45° ply in the carbon fiber spar caps with the 0° ply exhibited superior performance to the ±45° ply laminate in the glass plies.Combined with the finite element analysis of the blade structure,the similarities and differences between the comparison experiment and the simulation calculation,the reliability of the experimental conclusion was verified,and the man-made reason and system cause of the difference between the two were analyzed,which provided a reference for future research.This innovation is based on the blade aerodynamic design and structural design,in order to make research more convenient to put forward the method of model test.It can reflect the structural performance of the blade to a certain extent,and has engineering reference value for the safe operation of the actual blade.In the finite element analysis,the combination of simulation and experiment is realized by means of load step loading,which makes the simulation calculation as close as possible to the loading process in the experiment,which provides a new possibility for the comparative analysis of future experiments and calculations. |
PDF Full Text Request