Making fault

[Jason.Jonkman]

Dear Sebastian,

I would recommend compiling in debug mode and stepping through the solution within VS by adding breakpoints, clicking on Step Into, etc. I'm sure you can find information on how to do this in VS help. You could also post specific questions on OpenFAST issues, where more of the OpenFAST developers are active than in this forum, which tends to cater more towards usage of FAST / OpenFAST.

Best regards,

[Jason.Jonkman]

For others following this forum thread, the discussion around Sebestian's code changes has moved from here to OpenFAST issues: https://github.com/OpenFAST/openfast/issues/339.

Best regards,

[Hamidreza.Mor]

Dear Jason,

I am trying to make faults on FAST; Blade fault and Gearbox Fault.
I have two questions:
1) Blade Fault
AdjBlMs, AdjFlSt and AdjEdSt are the factors that i can change.
What is the difference between flap stiffness and edge stiffness?
How can i change blade stiffness?
Decrease the default value(=1) or increase?


2) Gearbox Fault
Can i "decrease" both Drivetrain torsional spring and Drivetrain torsional spring simultaneously for Gearbox Fault? Does it make sense?

Best Regards

[Jason.Jonkman]

Dear Hamridreza,

The flapwise direction is nominally normal to the chord and the edgewise direction is nominally parallel to the chord, so the flapwise stiffness is generally much less than the edgewise stiffness, except near the blade root. By "blade fault", I would guess you mean cracks in the composite fibers, which I would expect would result in a reduction in stiffness.

I'm not sure how a "gearbox fault" would be related to the drivetrain torsional spring and damping. But I would say that normally the damping is proportional to the stiffness in some way, so, if you change the stiffness, it is likely good to the change the damping proportionally as well.

Best regards,

[Hamidreza.Mor]

Dear Jason,
Thanks for your answer.
As you said for Blade crack simulation, i should reduce stiffness. I have a question:

For stiffness reduction, should i change both AdjFlSt = 1(Factor to adjust blade flap stiffness) and AdjEdSt = 1(Factor to adjust blade edge stiffness)?
or changing one of them is more appropriate for Blade crack?

Best Regards,

[Jason.Jonkman]

Dear Hamidreza,

I'm not an expert on that subject, but I would guess both the flapwise and edgewise stiffness would reduce as a result of cracks in the composite fibers.

Best regards,

[Hamidreza.Mor]

Dear Jason,

I want to change the dynamics of the pitch system by varying the damping factor( 0.6) and the natural frequencies( 11 rad/s) from their nominal
values.
where can i find these parameters?

Best Regards,

[Jason.Jonkman]

Dear Hamidreza,

I'm assuming you are referring to the baseline controller for the NREL 5-MW wind turbine; is this correct? The baseline controller for the NREL 5-MW wind turbine is implemented as a dynamic library in Bladed format (DISCON.dll). The parameters are hard coded within this dynamic library. You can change them by opening up the corresponding source file (DISCON.f90), changing the parameters, and recompiling the dynamic library.

Best regards,