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Use of UserProp

Posted: Tue Mar 30, 2021 1:43 am
by Simon.Wiedemann
Dear all,

with OpenFAST 2.3 a UserProp value was introduced for each airfoil table (before it was Ctrl i believe) together with AFTabMod. The intention was to enable control flaps deployed dynamically in the simulation controlled by the dll-controller.
https://openfast.readthedocs.io/en/main/source/user/api_change.html#openfast-v2-2-0-to-openfast-v2-3-0

Is it planned to enable the use of this UserProp value as static input given for each airfoil file or each aerodynamic station?
Idea is to use the thickness of the blade as an indicator which airfoil table to use or interpolate. As long as the characteristics of the airfoils are similar in one airfoil file linear interpolation between tables should yield sufficient results while decreasing preprocessing steps.

Best regards,
Simon

Re: Use of UserProp

Posted: Tue Mar 30, 2021 6:35 am
by Jason.Jonkman
Dear Simon,

The addition of UserProp in AeroDyn and the controls interfaces is to allow the user to interpolate between different airfoil data through the controller, e.g., to simulate trailing edge flaps or other airfoil flow-control technologies.

NREL has not been funded to implement interpolation of airfoil data based on thickness; it is generally recommend that the user use AirfoilPrep or AirfoilPreppy to preprocess the airfoil data before use in FAST / OpenFAST.

Best regards,