Fatigue Life Prediction Of Composite Materials For Wind Turbine Blade

Nowadays, human beings have to confront the energy problems and environmental problems in order to survive and develop. On the one hand, the demand of human beings for electricity is growing rapidly, and electricity shortage happens sometimes; on the other hand, the development and utilization of conventional energy sources restricts the human sustainable development. Therefore, the new energy is gradually concerned by people because of the demand for energy. Compared with the other new energy, the wind power has advantages of the long development history, reliable technology and high commercial value, so wind power will be one of the main developing directions of clean energy. By 2014, the global total installed capacity of wind power is more than 369.5GW. Due to the enormous scale of wind power industry, the high cost of blades which are the core component of wind turbines make up about a quarter to a third of the whole equipment cost, and the importance of the blades’ fatigue life which largely determine the life of the wind turbine, so the fatigue research on blades is of great practical significance.This paper proposes a prediction method of composite’s fatigue life for wind turbine blade. First, according to the fatigue conditions from GL2010 Certification, the writer quickly calculates the blade’s fatigue load spectrum by using GH- Bladed software. Second, the parameterized model of blade is created in the ANSYS finite element software with SHELL181 element to define composite material, and the writer gets fatigue stress spectrum through the transient analysis. Third, on the basis of the composite material s-n curve from GL2010 Certification, the fatigue analysis of multi component composite materials for wind turbine blade is done in FE- SAFE software.This method has three different aspects compared with the others:(1) the fatigue load spectrum bases on the fatigue condition from GL2010 Certification;(2) the fatigue stress spectrum is obtained by transient analysis, and can truly reflects the blade force under the fatigue wind condition;(3) the writer considers the multi component characteristics of composite materials, and inputs multi S/N curve to different materials when doing fatigue analysis. Finally, the calculation example shows that the life time calculation is in accord with the actual service life in practice.