Effect of Blade Torsion on Modeling Results for the Small Wind Research Turbine (SWRT)

Abstract

The small wind research turbine (SWRT) testing project was initiated with the goal of better characterizing both small wind turbine loads and dynamic behavior. The main purpose of the testing was to produce high quality data sets for model development and validation and to help the wind industry further their understanding of small wind turbine behavior, including furling. Previous papers have discussed modeling results for the SWRT using the FAST aeroelastic simulator. This paper summarizes modeling results from both the FAST and ADAMS aeroelastic simulators. The ADAMS model allows for blade torsional stiffness to be modeled, which is shown to significantly improve the agreement between model and test results for rotor speed and explain variances in previous comparisons between the SWRT FAST modeling results and the SWRT test data. The ADAMS model results also show that the aerodynamic pitching moment impacts the blade torsion more than the inertial forces.

Analysis of the passive yaw mechanism of small horizontal-axis wind turbines

“…Meanwhile, the tail will furl to a higher position, and its gravity can create a backposition-torque, which tends to pull the tail to the original position. Furling occurs when the moment exceeds the torque [6]. When the velocity reaches the trigger speed, the yaw moment and back-position-torque obtain static equilibrium and the axis of the rotor keeps in line with the wind shown in Figure 6.…”

Identification of torsional frequencies of a large rotor blade based on measurement and simulation data

“…With increasing length, also the shape of the rotor blades becomes more and more sophisticated, and torsional deformation plays an important role. The inclusion of torsional deformation increases significantly the concordance between models and test results [6]. Thus, wind turbine models need to correctly reproduce the measured torsional deformation of a rotor blade, especially for large turbines, and set-ups for reliable measurements need to be developed.…”