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OpenFAST / openfast

Main repository for the NREL-supported OpenFAST whole-turbine and FAST.Farm wind farm simulation codes.
http://openfast.readthedocs.io
Apache License 2.0
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Where is the data available or which script creates data? #573

Closed ai-aspirant closed 3 years ago

ai-aspirant commented 3 years ago

Hello everyone, I went through the documentation, couldn't find out which script creates data? On the NREL website, the pre-processor AirfoilPrep helps create the data for Aerodyn for example are present for many such instances. But which module here works as a preprocessor and how can the data be downloaded or even fetch all hte .dat files?

Thank you very much in advance.

thisismihir commented 3 years ago

Hi Jason, So do you mean that my GenPwr would mostly be constant for steady-state winds? If that's the case, then my output power is not even close to any power curves. Can I plot the power curves using these OpenFAST modules? Or would it require turbulent wind speeds only? Can I do that on Paraview?

Regards, Mihir

jjonkman commented 3 years ago

Dear Kirsten -- Miscellaneous variables can be considered local variables that are stored in framework types for computational efficiency gains. They can be functions of inputs, outputs, states, or parameters. The product of RtSpeed and RtAeroMxh should equal RtAeroPwr if the units are appropriate (RtSpeed should be in rad/s, not rpm).

Dear Mihir -- OpenFAST can do much more, but of course it can be used to compute a power curve. This topic has been discussed on our forum: https://wind.nrel.gov/forum/wind. I suggest searching there for guidance.

Best regards,

ai-aspirant commented 3 years ago

Dear Jason, Yes, I did convert it from rpm to rad/s, it still varies a little not a lot. It helped thanks. I had few other questions as well, I'll just try to sum those up.

  1. As per what I understood with your help, AeroDynamic Power is linked to Rotor Speed and Aerodynamic load in x-direction (also called as Rotor Torque as I was going through the forum you mentioned ). Basis this, the two variables which I mentioned as an input are actually the outputs of AeroDyn module, but I wanted to know which inputs are linked to these parameters(RtSpeed and Rotor Torque). I couldn't find the connection or even the equation as to which inputs are linked to the equation variables over here. I just came down to the _ADCalcOutput subroutine but no connections further. So just wanted to know about the links between the same.

  2. I came to know about the change in Electrical Generated Power Output as well from the forum i.e. GenPwr, do we have any input dependent on that as well similar to the previous questions? As, the formula that I came across for that is GenPwr = 0.001*y%ElecPwr

  3. Another thing I was trying to understand but having hard time was how the time-functions are initialised. I mean from 0 to 60 time functions having 168 for each time functions; basis that I was unsure as to how the variables might change, is that because of the placements of all the blades or a particular variable is changed such that my rest of the parameter deviates acoordingly or is it inter linked to something?

  4. Does OpenFAST support and provides a simulation for understanding failures in various components like gear-box, blades, rotor, etc?

  5. By any chance does OpenFAST supports recreating some particular variable in case one doesn't have a data for that?

My apologies for some rather trivial questions. I just wanted to make sure I am interpreting the outputs and the flow correctly. Thank you for all your time and effort.

Regards, Kirsten

jjonkman commented 3 years ago

Dear Kristen,

Here are my answers to some of your questions;

  1. It is important to distinguish between module-level inputs and outputs (related to how modules interact between each other in OpenFAST, also known as u and y in the modularization framework documentation and source code) and user-specified inputs and user-selected outputs (input parameters the user defines in an input file and what is written to the output file). Rotor speed is a module-level input to AeroDyn (meaning it is calculated by a different module (ElastoDyn) or set by the driver) and it is also possible to include rotor speed in the output file. Rotor torque is computed within AeroDyn and can written to the output file.

  2. The electrical power is computed by the ServoDyn module, dependent on which torque control or generator model is selected. The equation you state is just a conversion from Watt to kW.

  3. I don't understand your question.

  4. Various fault cases are supported, e.g., loss of pitch control and loss of torque control, as has been discussed on the forum. I would search there for more information.

  5. A few input parameters have default settings, indicated by the keyword "DEFAULT", but most require user specification. See the documentation and sample input files for more information.

Best regards,

SkyupChen commented 3 years ago

Dear @jjonkman,

I was able to use IECwind to generate the IEC ECD+R.wnd file and use WindType = 2, the simulation run through, but when I plot the hub height x-wind speed, I got something complete different from the IEC wind profile should be. Please see the screen shot below.

ecdwind_iecwind

This plot is taken from variable name "Wind1VelX". Am I outputting wrong signal or is there something wrong with inflow input file?

Many thanks in advance!

Best Regards,

jjonkman commented 3 years ago

This question has been asked and answered in a separate issue: https://github.com/OpenFAST/openfast/issues/815.

Best regards,