Fatigue Analysis of Wind Turbine Blade Made of Composite Material

Abstract

Currently, utilization of renewable energy sources is the major international attention to overcome the global warming. Wind energy which is generated from wind flow by wind turbine is one of a promising sources of renewable energy with significant potential. The majority failures of wind turbine blade are due to fatigue load on the components like fatigue failure of many other ordinary materials. Fatigue stresses are developed on the wind turbine blade due to change in wind speed and increasing other factors on the blade length. The main objective of this thesis research is to analyze a fatigue failure of a wind turbine blade made of composite materials (E-glass fiber) for horizontal axis wind turbine (HAWT) blade due to various loads occurring during operation. The main cause of fatigue of wind turbine blade; critical portion where stress acting area is maximum, aerodynamic effect on blade and stress distribution on the wind turbine blade are identified and determined by ANSYS. 3-D model is developed by CATIA with NACA 4412 of air foil profile and fatigue analysis of the typical wind turbine blade has been analyzed using commercially available FEM and CFD Fluent with ANSYS. This study is conducted to get the maximum stressed region and critical area of the blade by aerodynamic forces. The fatigue analysis is conducted by both analytical and simulation methods. The result from the analysis show that the wind turbine blade with given typical parameter is determined and operating for minimum of eleven years. Generally, from CFD result leading edge of at blade tip and from static structural analysis root/hub of the blade is highly stressed as a result the gradual failure which is called fatigue failure is determined and discussed with comparative loads effects.