文档介绍：Composite Structures 74 (2006) 332–342
pstruct
Simulation of fatigue failure in a posite wind turbine blade
Mahmood M. Shokrieh *, Roham Rafiee
Composites Research Laboratory, Mechanical Engineering Department, Iran University of Science and Technology, Narmak, Tehran 16844, Iran
Available online 13 June 2005
Abstract
Lifetime prediction of a horizontal axis wind posite blade is considered. Load cases are identified, calculated and
evaluated. Static analysis is performed with a full 3-D finite element method and the critical zone where fatigue failure begins is
extracted. Accumulated fatigue damage modeling is employed as a damage estimation rule based on generalized material property
degradation. Since wind flow (loading) is random, a stochastic approach is employed to develop puter code in order to sim-
ulate wind flow with randomness in its nature on the blade and subsequently each load case is weighted by its rate of occurrence
using a Weibull wind speed distribution.
Ó 2005 Elsevier Ltd. All rights reserved.
Keywords: Composites; Finite element; Stochastic; Wind turbine blade; Damage; Failure analysis
1. Introduction Generally, wind turbines are fatigue critical machines
and the design of many of ponents (especially
Pollution free electricity generation, fast installation blades) are dictated by fatigue considerations. Several
missioning capability, low operation and main- factors expose wind turbine blades to the fatigue phe-
tenance cost and taking advantage of using free and nomena which can be summarized as shown below [1]:
renewable energies are all advantages of using wind tur-
bines as an electricity generators. Along with these 1. Long and flexible structures
advantages, the main disadvantage of this industry is 2. Vibrations in its resonant mode
the temporary nature of wind flow. Therefore, using reli- 3. Randomness in the load spectra due to the nature of
able and efficient equipment is necessary in order to get the wind
as muc