Coordinate system Q_TFA1

Wind & Water Structural Analysis
1

Dear all,

I have a query regarding the degrees of freedom (dof) Q_TFA1 and Q_T1SS of the linear state-space system. Specifically, I am curious to know if these degrees of freedom correspond to the tower top coordinate system (xp, yp, zp) and therefore do not yaw with the nacelle.

Traditionally, the fore-aft direction aligns with the main wind direction in a local coordinate system that rotates with the yaw of the turbine. However, I would like clarification on whether I need to perform a coordinate transformation if I intend to examine the global tower displacement in the x and y directions.

Your insights on this matter would be greatly appreciated.

Thank you in advance for your assistance.

Best regards,
Judith

2

Dear @Judith.Hess,

Your understanding is correct. The tower-bending degrees of freedom in ElastoDyn that you are referring to do not yaw with the nacelle. They do, however, yaw with the platform, if the platform degrees of freedom are enabled.

Best regards,

3

Dear @Jason.Jonkman,

Thank you so much!

Best regards,
Judith