A UDF to stop an unsteady run calculation based on the pressure in the fluent

smh7 · December 9, 2023, 08:41

Hello
I have an unsteady 2D simulation in Fluent that needs a UDF to stop an unsteady run.
This UDF should calculate the minimum pressure (according to the pressure versus time diagram) and stop the run when it reaches the minimum pressure.
I think it's not difficult to write the UDF code, but I can't find of a way to import it into Fluent.
If anyone has information about this (writing the UDF code and importing it to Fluent), I would be grateful if you could help me.

(I have attached a picture of the step that needs to be stopped.)

PrasantKaredla · December 11, 2023, 04:53

Hi,

You must hook your UDF in the Execute on Demand. There you can see the options to start and stop the simulations.

Best Regards,
Prasant K

Julian758 · January 1, 2024, 00:32

Hello,
I'm working on an unsteady 2D simulation in Fluent and require a UDF to halt the run based on a minimum pressure threshold from a pressure versus time plot. While I'm confident in creating the UDF code, I'm struggling with the process of importing it into Fluent. Any guidance on both coding the UDF and importing it into Fluent would be immensely appreciated. Thank you.

PrasantKaredla · January 2, 2024, 05:14

Hi,

It is a simple process, First of all, You should have Visual C++ installed on your computer.
Ansys Fluent detects the VC++ software if it is installed on your computer.

Once this process is done, then you need to compile your UDF in fluent.

If no errors are found while compiling, Then your UDF works perfectly.

I don't have the software now. If you have the software, please reach out to me on prasant.karedla@outlook.com. I will show you how to compile the UDF in Ansys Fluent via Teams calling or Google meet.

Fastest way is to refere Ansys Fluent Documentation on How to compile UDF.
Ansys have perfect documentation on Compiling UDF's and explanation of different Macro's.

Best Regards,
Prasant Karedla

January 1, 2024, 00:32	2D simulation in Fluent and require a UDF	#3
Julian758 New Member NO Join Date: Nov 2023 Posts: 1 Rep Power: 0	Hello, I'm working on an unsteady 2D simulation in Fluent and require a UDF to halt the run based on a minimum pressure threshold from a pressure versus time plot. While I'm confident in creating the UDF code, I'm struggling with the process of importing it into Fluent. Any guidance on both coding the UDF and importing it into Fluent would be immensely appreciated. Thank you.

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December 11, 2023, 04:53		#2
PrasantKaredla New Member Join Date: Sep 2020 Posts: 16 Rep Power: 5	Hi, You must hook your UDF in the Execute on Demand. There you can see the options to start and stop the simulations. Best Regards, Prasant K

January 2, 2024, 05:14		#4
PrasantKaredla New Member Join Date: Sep 2020 Posts: 16 Rep Power: 5	Hi, It is a simple process, First of all, You should have Visual C++ installed on your computer. Ansys Fluent detects the VC++ software if it is installed on your computer. Once this process is done, then you need to compile your UDF in fluent. If no errors are found while compiling, Then your UDF works perfectly. I don't have the software now. If you have the software, please reach out to me on prasant.karedla@outlook.com. I will show you how to compile the UDF in Ansys Fluent via Teams calling or Google meet. Fastest way is to refere Ansys Fluent Documentation on How to compile UDF. Ansys have perfect documentation on Compiling UDF's and explanation of different Macro's. Best Regards, Prasant Karedla