I want to ask you about difference of experimental data and simulation results.
The experiment and input of FAST are the same.

Input: 2-blade downwind, hub height: 1.6m, rotor radius: 0.8m, mainstream velocity: 8m/s
parameters of bade and tower of FAST are used from other experiment.

The cyclic pitch control was used in this experiment.
For pitching moment: phase of pitch angle = 45 deg, both results are the same.
phase of pitch angle = 0 deg, there is difference.
Why is there difference?
Simimlarly with Yaw moment?

I’m so sorry, I told unclearly. Can you explain the difference of simulated results and experimental data?
Parameters of bade and tower of FAST are used from other experiment.

1- I used cyclic pitch control to decrease load of WT. Pitch angle is defined as in the attached file
2- Pitch moment and yaw moment are considered on the rotor surface.
pitch moment on the x-axis, yaw moment on the z-axis.

To me, the FAST results make sense because at 45-deg phase angle for the cyclic pitch angle, I would expect identical magnitudes of the cyclic pitch and yaw moments, which is what FAST is showing. However, the experimental data does not show this consistency.

I’m so sorry, because I didn’t understand clearly.
Can you explain clearly for me?
What is the reason caused in that phenomenon?

For the pitch moment:
At phase of pitch angle is 45 deg, there is the same results both the experiment and simulation.
At phase of pitch angle is 0 deg, there is large difference.

For the yaw moment:
At phase of pitch angle is 0 deg, there is slight difference of the experiment and simulation.
At phase of pitch angle is 45 deg, there is large difference of the experiment and simulation.

Note: in the two figures, the pitch angle is negative, the difference is larger than positive pitch angle.

I don’t really know why the experimental results are different from FAST. I was simply pointing out the inconsistency in the experimental results at 45-deg phase angle, where I would expect the magnitude of the the pitch and yaw moment amplitudes to be identical, which is what FAST is showing, but is not what the experimental data is showing.

I would review the experimental set-up to understand why it is showing this inconsistency at 45-deg phase angle.