Bending-Twisting Coupling in wind turbine blades

Hi all,
Many modern researches are discussing the idea of using Bending-Twisting coupling phenomenon in composite materials (that results from non-symmetric composite layups) in passive control or even improvement of rotor performance. I wanted to ask if FAST and its pre-processors (like: PreComp and BModes) can simulate those blades and show accurate results?

Dear Khaled,

PreComp can model blades with bend-twist coupling, but FAST v7 (or ElastoDyn in FAST v8) and BModes assumes blades mades out an isotropic material.

We are making good progress on the development of our new BeamDyn module for FAST v8. This module will greatly enhance FAST’s ability to model blade structural dynamics. BeamDyn is based on geometrically exact beam theory (GEBT) and implemented using spectral finite elements. The model includes full geometric nonlinearity; bending, torsion, shear, and extensional DOFs; anisotropic material couplings (full 6x6 mass and stiffness matrices, including bend-twist coupling); sectional offsets; and initially curved/swept blades. We are currently making it more user-friendly and are in the process of coupling it to FAST v8. We then plan an extensive verification effort, will document it, and release it. Our next release of FAST v8 is happening at the end of June, but BeamDyn will not yet be included in this release. Instead, the first public release of BeamDyn will occur later this year.

Best regards,

Dear Jason,
It is a very good news about FAST v8 and BeamDyn and their release date. I hope they will be released very soon because I need it for my research. But is there any other way to take Bending-Twisting Coupling effect in simulation process that I can use until these new modules are released ?. Do you have any advice ?. Thank you very much for your quick response and keep up good work. Good luck.

Dear Khaled,

As I said, the FAST v8 release that includes BeamDyn will come out later this year. The exact release date has not been set. Without BeamDyn or other modifications, FAST by itself cannot be used to model blades with bend-twist coupling.

Until this new release of FAST is available, one option you have if you own MSC.ADAMS, is to use the FAST-to-ADAMS preprocessor to generate the ADAMS model. The FAST-to-ADAMS preprocessor supports blades with bend-twist coupling.

Best regards,