Impact of blade structural and aerodynamic uncertainties on wind turbine loads

Abstract

Offshore wind power has been in the spotlight among renewable energy sources. The current trends of increased power ratings and longer blades come together with the aim to reduce energy costs by design optimisation. The standard approach to deal with uncertainties in wind‐turbine design has been by the use of characteristic values and safety factors. This paper focusses on modelling the effect of structural and aerodynamic uncertainties in blades. First, the uncertainties in laminate properties are characterised and propagated in a blade structural model by means of a Monte Carlo simulation. Wind tunnel measurement data are then used to define the variability in lift and drag coefficients for both clean and rough aerofoil behaviour, which is then used to extrapolate rough behaviours throughout the blade. A stochastic spatial interpolation parameter is used to define the evolution of the degradation level. The combined effect and the variance contribution of these two uncertainty sources in turbine loads is finally defined by aeroelastic turbine simulation. This research aims to provide a framework to deal with uncertainties in wind‐turbine blade design and understand their effects in turbine behaviour.

Transforming Laser-Scanned 750 kW Turbine Surface Geometry Data into Smooth CAD for CFD Simulations

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Buckling behavior of rotor blade sandwich panels with spatially distributed material uncertainties

“…Due to their large size and the low level of automation in the manufacturing process, finished rotor blades have a relatively high level of structural uncertainty. These uncertainties include manufacturing defects, positional alignment errors, and material property uncertainties [2].…”

“…The face sheets' material distributions are completely uncorrelated, allowing for both local and global asymmetry. The results are discussed in comparison to the standard deviation of the material properties, which was taken from the work of Gonzaga et al [2].…”

Experimental testing method to characterise the drapability of UD non-crimp fabrics used in wind turbine blades

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