modal analysis of NREL 5MW wind turbine

Wind & Water Structural Analysis
1

Dear all

I have built the finite element model for NREL 5MW wind turbine in ANSYS in order to do dynamic analysis. I use parameters and information provided in prod-ng.sandia.gov/techlib-noau … 132569.pdf. The natural frequency of 1st edgewise bending is 1.578 in my ANSYS model, while the reference value is 1.06, the error is around 50%. Other modes are accurate with acceptable errors (around 2%). May I know if any other encounters similar probblems? And are there any lab tests for the NREL 5MW wind turbine?

I would be appreciated it if you could reply. Thank you :slight_smile:

Best regards
Zimo

2

Dear Zimo,

I’m not aware if others have had similar comments, but I’ll let others respond.

Does your ANSYS model include the effect of blade structural pretwist, which couples flap and edge bending? If not, perhaps this could explain the discrepancy?

A full-scale NREL 5-MW turbine has never physically been built, and most physical models at model scale that I’m aware of (for wind tunnel or wave tank testing) use a rigid rotor.

Best regards,