Validation of the AeroDyn subroutines using NREL unsteady aerodynamics experiment data

Abstract

Completion of the full‐scale wind tunnel tests of the NREL Unsteady Aerodynamics Experiment (UAE) phase VI allowed validation of the AeroDyn wind turbine aerodynamics software to commence. Detailed knowledge of the inflow to the UAE was the bane of prior attempts to accomplish any in‐depth validation in the past. The wind tunnel tests permitted unprecedented control and measurement of inflow to the UAE rotor. The data collected from these UAE tests are currently under investigation as part of an effort to better understand wind turbine rotor aerodynamics in order to improve aeroelastic modelling techniques. Preliminary results from this study using the AeroDyn subroutines are presented, pointing to several avenues towards improvement. Test data indicate that rotational effects cause more static stall delay over a larger portion of the blades than predicted by current methods. Despite the relatively stiff properties of the UAE, vibration modes appear to influence the aerodynamic forces and system loads. AeroDyn adequately predicts dynamic stall hysteresis loops when appropriate steady, 2D aerofoil tables are used. Problems encountered include uncertainties in converting measured inflow angle to angle of attack for the UAE phase VI. Future work is proposed to address this angle‐of‐attack problem and to analyse a slightly more complex dynamics model that incorporates some of the structural vibration modes evident in the test data. Copyright © 2002 John Wiley & Sons, Ltd.

Real-Time Hybrid Model Testing of a Braceless Semi-Submersible Wind Turbine: Part II — Experimental Results

“…AeroDyn [20] is a wellknown implementation of the blade element/momentum (BEM) and generalized dynamic wake (GDW) methods, which has been validated against experimental data [21]. BEM was applied for mean wind speeds of 8 m/s, while GDW was applied for all other wind speeds.…”

A study on rotational effects and different stall delay models using a prescribed wake vortex scheme and NREL phase VI experiment data

“…There has been some discussion as to how drag is affected by the stall delay phenomenon (see e.g. Laino et al 34 ). The drag increase suggested by the NREL measurements in Figure 4, except near the tip of the blade, is in agreement with the most recent theoretical works on the subject.…”

Estimating the angle of attack from blade pressure measurements on the National Renewable Energy Laboratory phase VI rotor using a free wake vortex model: yawed conditions

“…The pressures were integrated along the blades to yield the local blade normal and tangential aerodynamic loads. These data have been analysed by various researchers and used for bases of comparison with state-of-the-art aerodynamic codes modelling both axial [15][16][17][18][19][20][21] and yawed conditions. [20][21][22][23] A major diffi culty with analyzing experimental measurements is to determine the angle of attack at the different blade sections.…”