Relating turbulence to wind turbine blade loads - Parametric study with multiple regression analysis

Different wind parameters are studied to find a set that is most useful in estimating fatigue loads on wind turbine blades. The histograms of rainflow counted stress ranges are summarized through their first three statistical moments and regression analysis is used to estimate these moments in various wind conditions. A systematic method of comparing the ability of different wind parameters to estimate the moments is described and results are shown for flapwise loads on three HAWTs. In the case of two of these turbines, the stress ranges are shown to be highly correlated with a turbulence measure obtained by removing a portion of the low-frequency content of the wind.

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A Comparison of Predicted Wind Turbine Blade Loads to Test Measurements

Journal of Solar Energy Engineering ◽

10.1115/1.3268254 ◽

1988 ◽

Vol 110 (3) ◽

pp. 180-186 ◽

Cited By ~ 1

Author(s):

A. D. Wright ◽

R. W. Thresher

Keyword(s):

Wind Turbine ◽

Turbine Blade ◽

Wind Turbine Blade ◽

Scale Model ◽

Bending Moments ◽

Energy Research ◽

Wind Speeds ◽

Loads Analysis ◽

Wind Tunnel Data ◽

Blade Loads

The accurate prediction of wind turbine blade loads and response is important in predicting the fatigue life of wind machines. At the SERI Wind Energy Research Center, a rotor code called FLAP (Force and Loads Analysis Program) is currently being validated by comparing predicted results to machine measurements. The FLAP code has been modified to allow the teetering degree of freedom. This paper describes these modifications and comparisons of predicted blade bending moments to test measurements. Wind tunnel data for a 1/20th scale model will be used to compare FLAP predictions for the cyclic flap-bending moments at the 33 percent spanwise station for three different wind speeds. The comparisons will be made for both rigid and teetering hubs. Currently, the FLAP code accounts for deterministic excitations such as wind shear, tower shadow, gravity, and prescribed yawing motions. Conclusions will be made regarding the code’s accuracy in predicting the cyclic bending moments.

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A parametric study of flutter behavior of a composite wind turbine blade with bend-twist coupling

Composite Structures ◽

10.1016/j.compstruct.2018.09.064 ◽

2019 ◽

Vol 207 ◽

pp. 764-775 ◽

Cited By ~ 5

Author(s):

Praveen Shakya ◽

Mohammed Rabius Sunny ◽

Dipak Kumar Maiti

Keyword(s):

Wind Turbine ◽

Turbine Blade ◽

Parametric Study ◽

Wind Turbine Blade

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Parametric study on off-design aerodynamic performance of a horizontal axis wind turbine blade and proposed pitch control

Energy Conversion and Management ◽

10.1016/j.enconman.2015.01.048 ◽

2015 ◽

Vol 93 ◽

pp. 349-356 ◽

Cited By ~ 26

Author(s):

Z. Najafian Ashrafi ◽

M. Ghaderi ◽

A. Sedaghat

Keyword(s):

Wind Turbine ◽

Turbine Blade ◽

Parametric Study ◽

Aerodynamic Performance ◽

Wind Turbine Blade ◽

Horizontal Axis ◽

Horizontal Axis Wind Turbine ◽

Pitch Control

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On the wind turbine blade loads from an aeroelastic simulation and their transfer to a three-dimensional finite element model of the blade

Wind Engineering ◽

10.1177/0309524x19849861 ◽

2019 ◽

Vol 44 (6) ◽

pp. 577-595

Author(s):

Louis-Charles Forcier ◽

Simon Joncas

Keyword(s):

Finite Element ◽

Finite Element Model ◽

Wind Turbine ◽

Turbine Blade ◽

Three Dimensional ◽

Element Model ◽

Wind Turbine Blade ◽

Dimensional Finite Element ◽

Three Dimensional Finite Element ◽

Blade Loads

This article first presents a description of the different load types to which a wind turbine blade is subjected. Analytical equations are derived to express blade loads from operation parameters of the wind turbine (rotor and nacelle velocities and accelerations; pitch, coning, tilt, and azimuth angles; blade mass properties; turbine geometry). This allows a better understanding of the contribution of each of these parameters to the total load on a blade. A difficulty arises for transferring the loads computed by an aeroelastic model (a one-dimensional model of the blade) to a three-dimensional finite element model of the blade. A method is proposed for that purpose. It consists in applying the aerodynamic loads using RBE3 elements and applying gravitational and inertial loads as volume forces. Finally, an example of this method used for the design of a 10 kW wind turbine blade is presented.

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