Deformed Blade and rigid blade comparison

Wind & Water Structural Analysis
1

Hi All,

I am new to FAST, so please forgive me if the question is too simple.

I am wondering that can FAST BeamDyn generate outputs of each blade section (2D airfoil) after the aerodynamic load (AeroDyn) to see the aeroelastic effect?

My goal is to see the difference between deformed blade and rigid blade along the rotor blade.

Thanks.

2

Dear Daniel,

I’m not sure I understand your question, but FAST does includes aero-elastic coupling between the structural (BeamDyn or ElastoDyn) and aerodynamic (AeroDyn) modules. BeamDyn can output the applied loads, reaction loads, deflections, velocities, and accelerations at each analysis node along the blade.

Best regards,

3

Hi Dr.Jason,

Thank you for your response. My intention is to compare the 2D sectional geometry of rigid blade and deformed blade along with the blade sections. The picture is one of the example from the reference. Note that the reference uses CFD and FEM for the aerodynamic and aeroelastic analysis.

Capture2.JPG
Capture2.JPG1100×459 117 KB

So, I am wondering that what output (from AeroDyn or BeamDyn) can provide enough information to re-construct 2D sectional views of the deformed blade.

Thank you for your help.

Reference: Hany, N., W. Darris, and M. Walter, Structural Dynamics of Small Wind Turbine Blade under Aerodynamic Loading, in 44th AIAA Aerospace Sciences Meeting and Exhibit. 2006, American Institute of Aeronautics and Astronautics.

4

Dear Daniel,

BeamDyn can output the deflections (3 translations, 3 rotations) at each analysis node (2D cross section) along the blade of the deflected beam relative to the root. See the BeamDyn documentation for more information.

Please note that BeamDyn is a beam model, so to be clear, the 2D cross section is not assumed to have warping in the plane of the cross section i.e. the 2D airfoil profile will not change with deflection. (Out-of-plane warping is not modeled by BeamDyn either, but some assumption of out-of-plane warping was likely used in the 2D cross-sectional analysis that is required as a preprocess to derive the 6x6 cross-sectional stiffness matrices used as input to BeamDyn.)

Best regards,