WISDEM "Design of Experiment"

Wind & Water Computer-Aided Engineering Software Tools
1

Hi. We have a WISDEM related question–potentially for @Pietro.Bortolotti or @Garrett.Barter.

We are trying to perform a WISDEM based parametric study. We are trying to use the tools as much as possible in the way they are designed to be used.

I see in the WISDEM examples, there is:
-Example 1: A for loop based DOE
-Example 13: The “DOE” example

There isn’t documentation for Example 13. We are wondering more on the intent of this example. It appears as though OpenMDAO creates and runs a DOE. However, I am not seeing more than one resulting turbine set of parameters outputted.

Is the DOE option in Example 13 just create multiple starting locations for the optimization and then a single optimal wind turbine design (and associated parameters) is selected and outputted?

Insights on the intent of this example is much appreciated. Also, if there is a suggested way to leverage the OpenMDAO DOE capabilities used by WISDEM to perform a parameter exploration, that would be of interest.

Thank you; I much appreciate your help and insights!

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Hi,
thanks for the post. I quickly met with @Garrett.Barter and @John.Jasa to put together the best answer. To start, we should admit that Garrett and I don’t use the DOE functionality very often, and that’s why Example 13 comes without documentation. It comes from older research work, and we’ll make sure to add some documentation moving forward.
Now to your actual questions:

  • WISDEM is not truly setup to run DOEs. As it stands, example 13 will run 5 cases where the chord distribution is varied (flag True) across 8 points along blade span where each point is drawn from a uniform distribution perturbing the baseline chord distribution between 20% of its original value and 200% of the original value. The user should turn the OpenMDAO recorder and this will record the values of the inputs (the points controlling the chord) and the figure of merit. WISDEM will however only save the outputs for the 5th and last iteration (this is probably what you are puzzled about…).
  • We do run WISDEM iteratively much more often, but we construct our own for loops around WISDEM. Often times, the call to WISDEM within the for loop is an optimization. Note that WISDEM supports MPI calls for parallelization. That comes useful in large studies.
  • To leverage the DOE capabilities of OpenMDAO within WISDEM, rely on the OpenMDAO recorder and skip the writing of the outputs here

We hope this provides some clarity!