复合材料风电叶片细观失效准则及其损伤演化

Microscopic Failure Criterion and Damage Evolution of Composite Material Wind Turbine Blades

针对复合材料风电叶片在实际使用过程常常出现损伤的问题,提出一种基于细观失效准则的复合材料细观损伤分析模型。采用通用单胞模型(Generalized method of cells,GMC)对具有周期性的单向复合材料层合板进行细观建模,并且引入基于Huang模型的细观失效准则和刚度退化准则,从细观层面上分别对纤维和基体的失效模式进行表征,对4种单向复合材料层合板的渐进损伤过程进行数值模拟。在试验验证过程中,先对两种不同状态(含损伤和无损伤)的复合材料风电叶片进行了静力加载试验,采用光纤光栅传感器监测损伤对风电叶片应变的影响;然后通过典型的单向层合板的拉伸破坏试验得到的应变曲线来验证本算法的有效性。结果表明:当复合材料风电叶片中存在损伤时,将降低其承载能力,并且应变值变化明显,可以通过应变来监测叶片的健康状态;提出的模型能够通过得到的应变曲线准确地预测单向复合材料层合板的力学性能和破坏强度值。

For the problem that composites wind turbine blades always occurre damage,a model,which is a composite microscopic damage analysis model based on a microscopic failure criterion,is proposed.The generalized method of cells （GMC） is employed to model for unidirectional composite laminated plates with periodic microstructures.A microscopic failure criterion based Huang model is also introduced.The failure mode of fiber and matrix are characterized respectively microscopically.The progressive damage of four unidirectional composite laminated plates is simulated numerically.Static loading experiments are also carried on wind turbine blades of composite with two different states （damaged and undamaged） and the influence of the damage on the strain of the wind turbine blades is monitored by the fiber bragg grating.The strain curve get through the failure experiment of the typical unidirectional laminate is used to verify the effectiveness of the algorithm proposed.The experimental analysis shows that the carrying capacity of the composite wind turbine blades will reduce when it is damaged,and their strain curve can be used to monitor the health statement of wind turbine blades.The proposed model can accurately predict the mechanical properties and breaking strength values of unidirectional composite plates.