Reliability of Wind Turbine Blades: An Overview of Materials Testing

The structural reliability of wind turbine components can have a profound impact on both the profitability and reputation of a wind turbine manufacturer or supplier of wind turbine components. The issue of reliability is of critical concern when large wind farm co-operatives are considered, and when wind turbines are located in remote regions where the cost of inspections and repairs can be very high. From a structural viewpoint, wind turbine blades are subjected to very complex loading histories with coupled deformation modes. The long-term reliability of wind turbine blades requires an understanding of how damage develops in composite structures, composite materials and adhesives. Designing reliable wind turbine blades also requires the further development of laboratory scale and full scale test methods to evaluate the structural response and durability of new materials under various loading and environmental conditions. This paper highlights recent advances in methods used to characterize adhesive joints in wind turbine blades and the manner in which laboratory data is used to predict the structural response of wind turbine blades.

[1]  A. Evans,et al.  A Test Specimen for Determining the Fracture Resistance of Bimaterial Interfaces , 1989 .

[2]  Y. Weitsman,et al.  A modified specimen for evaluating the mixed mode fracture toughness of adhesives , 2001 .

[3]  A. Buchman,et al.  Characterization of the mode I fracture energy of adhesive joints , 2006 .

[4]  J. H. Crews,et al.  Redesign of the Mixed-Mode Bending Delamination Test to Reduce Nonlinear Effects , 1992 .

[5]  A. Lystrup,et al.  Composite materials for wind power turbine blades , 2005 .

[6]  Jakob Wedel-Heinen,et al.  Type approval scheme for wind turbines. Recommendation for design documentation and test of wind turbine blades. , 2002 .

[7]  B. Hayman,et al.  Materials Challenges in Present and Future Wind Energy , 2008 .

[8]  U. Stigh Damage and crack growth analysis of the double cantilever beam specimen , 1988 .

[9]  Z. Suo,et al.  Mixed mode cracking in layered materials , 1991 .

[10]  Jakob Wedel-Heinen,et al.  New guidance for the development of wind turbine blades , 2005 .

[11]  H. Chai Deformation and fracture of particulate epoxy in adhesive bonds , 1995 .

[12]  Bent F. Sørensen,et al.  Measurement of Interface Fracture Toughness of Sandwich Structures under Mixed Mode Loadings , 2007 .

[13]  Knut O. Ronold,et al.  Calibration of partial safety factors for design of wind-turbine rotor blades against fatigue failure in flapwise bending , 1996 .

[14]  Bent F. Sørensen,et al.  DCB-specimen loaded with uneven bending moments , 2006 .