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DonQuijote January 2, 2013 12:20

Interaction between Fluent models
Hi all :)

Does anybody know if it is possible interaction between two or more fluent models?

For example, I want to use data from model1 to use as boundary condition in model2, that for each time step, so the sequence would be as follow.

- Reach convergence in model1 at tstep1, save data to be used in model2
- Reach convergenge in model 2 at tstep2 (with BC from model1 data), save data to be used in model1.
- Follow previous steps until a certain convergence is reached in both models.
- Proceed with nex tstep

So, do you know if there is a some routine to do it without closing a model for opening the other? The target is to keep open both to not to waste time, and compute the mentioned sequence automatically.

Thank you for your help!

msaeedsadeghi January 3, 2013 02:43

It may be possible using Ansys Workbench

DonQuijote January 3, 2013 03:09

Thank you for your answer. I'll take a look to the workbench guide

DonQuijote January 3, 2013 07:56

I have been reading the capabilities of Workbench, and the only I have found, similar to my purpose, is the 'System Coupling' component, but it only can couple wall forces in Fluent (it is designed for multiphysics...). :(

So, could the problem be solved using some UDF macro? Remind that the main purpose is to open a fluent case without close the other, and to 'jump' between both..

Yanlong Li January 4, 2013 08:29

I am so interested in your case. I think you can udf in both models, like output the converged values of model-1 as a file(the name should be changed depend on time if your model is unsteady), which will be used in modle-2. in the udf of modle-2, use a recycl code (such as if (exit (file of model-1)) read it, else wait). the model-1 is same. :D

DonQuijote January 7, 2013 08:15

Thank you for your comment!

But I think that the main problem is the 'wait' order. How the model can wait until the other has finished? I'm totally newbie in C code, and I really don't know if it is feasible...

Thanks again Yanlong Li ;)

Yanlong Li January 7, 2013 20:49

you can just write the code as follow:

exist_p = 0;
while (exist_p ==0)
if exit("file") /* Here, I forgot the code in C, it is "exist" in MATLAB, you can find yourself.*/
exist_p =1;
@@@@@ /* when it come to this line, it means the file is exist, and do want you want.

/*Acutally, there is a code "wait(5)" in Matlab, which means wait for 5 seconds, but I do not whether it's same in C. if it do not have, the code mentioned above is OK.*/

Hope it help.

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