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Modify parameter from scheme or UDF

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Old   May 22, 2019, 07:47
Default Modify parameter from scheme or UDF
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Théophile Schenker
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Hello !

I am creating a database to train a deep neural network that will give lift and drag forces, knowing pressure measurements, for a simple 2D airfoil shape (proof of concept).

I am using DesignPoints to run the simulation with various angles of attack and velocity magnitudes. The simulations are sent to a remote solve manager.

The geometry is constant, and the direction of the flow varies (to change the angle of attack).

At first, I am doing this in steady state. Here the inputs (angle of attack, magnitude) are workbench variables, and the output (pressure profile, drag, lift, residuals...) are written to a file using a UDF. This all works fine.

My problem comes when going to transient: I want to read input files to define the transient input velocity for each time step. I think I can do this easily with the DEFINE_PROFILE function. But I also need to change the gravity as a function of the angle of attack. How can I change the gravity (the option in fluent general tab) from the UDF ? In steady state I use a workbench parameter. But in transient it should change during the simulation.

More generally, is it possible to modify a workbench input parameter from fluent during a simulation ? (using udf or scheme)

Thank you very much in advance !
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Old   May 22, 2019, 23:41
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Alexander
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AlexanderZ will become famous soon enoughAlexanderZ will become famous soon enough
I don't know about UDF, seems its not available , but in scheme:
Code:
(format #f "define operating-conditions gravity yes 0 0 1")
for journal:
Code:
(ti-menu-load-string (format #f "define operating-conditions gravity yes 0 0 1"))
It will make gravity in Z-direction 1[m/s2]

best regards
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Old   May 24, 2019, 19:45
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Théophile Schenker
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Thank you very much ! I'll try this.
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Old   April 14, 2021, 12:54
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saeed akhavan
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Hi Théophile.
You can disable gravity and use momentum source term instead.
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