[Tensian]

Dear CFX users:

I am a beginner in CFX transient simulations. I would like to do the following:

Let us imagine two transient simulations in the same CFC case (for example Transient1 and Transient2). I have defined also two configurations in Simulation Controls (Config 1, associated with Transient 1 and Config 2 associated with Config 2). I would like to use the results of Config 1 as initial conditions of Transient 2 EXCEPT in one of the domains (I want to input a temperature).

I am able to use Config 1 as input for Transient 2, but I need to repatch one of the domains to a fixed temperature and I can't figure out how to tell CFX to do this.

IN FLUENT you run simulation and then you are able to stop, repatch one domain and continue with computation. How can I do this in CFX?

Thanks in advance for your support.

All the best,

Tensi

[Opaque]

You can already define the initialization step per domain.

However, you need an option to initialize to your desire value regardless of the value in the input file, correct ? That option is hidden from the UI, but you can try it and see if it works for you.

You may already have something like

TEMPERATURE:
Option = Automatic with Value
Temperature = MyNewTemp
END

Change it to

TEMPERATURE:
Option = Value
Temperature = MyNewTemp
END

Note that if the run is restarted it will re-initialize it again. You must revert it back to Automatic with Value.
Hope the above helps,

[Tensian]

Hi Opaque and thanks for your fast reply.

I think I am not understanding your tip.

What I want to do is:

Simulation 1 (10 seconds)
Domain1: T0=18
Domain 2: T0=160
Domain 3: T0=25
Domain 4: T0=600

Save the results, so now I have:

Domain1: T10=computed values for T in Domain 1
Domain 2: T10=computed values for T in Domain 2
Domain 3: T10=computed values for T in Domain 3
Domain 4: T10=computed values for T in Domain 4

Simulation 2 (10 seconds)

Domain 1:T0=T10=contours of computed (and saved) temperature in Domain 1
Domain 2:T0=T10=contours of computed (and saved) temperature in Domain 2
Domain 3:T0=contours of computed (and saved) temperature in Domain 3

Domain 4:T0=600ºC

I would like to repeat this each 10 seconds.

So, do you mean that if I create 2 brunches in the same CFX case (duplicate) but in the second brunch I change from automatic with value to automatic in all domains except the one I want to put at 600ºC then all domains will be updated to the computed temperature except the one that is still fixed to Automatic with value?

This sounds a bit weird, but I will give a try.I was thinking in something in CFX Solver manger, not in CFX Pre...

Thank you for your suggestions.

Kind regards,

Tensi

[Tensian]

Well, after giving a try to Opaque's suggestion, I think the problem reamains unsolved.

I am not sure if I am doing something wrong, but it seems that after reading the value specified using the Value option, CFX reads the result of the previous analysis, thus overwriting the previous value. So at the end, I am using again the numerical values computed in the new analysis in all defined domains.

What do you think guys? Am I doing something wrong? Or maybe CFX is not able to deal with something like this? In FLUENT is quite easy, so I guess CFX should allow this situation as well.

Thanks in advance for any comment!

Regards,

Tensi

[Tensian]

I have to apologize, but I was completely wrong.Opaque's suggestions were exactly the key!

I was postproccesing in CFD-post the wrong surface. If you use Command editor or you edit the .ded file in CFX-solver manager, changing form "Automatic with value" to "Value" in the desired domain will allow to use initial conditions from a previous file but just changing one domain to the "Value" specified. This can be seen by computng volumeAverage of the domain in the corresponmding time steps and/or .res files.

So thank you very much for the support! And sorry for my confusing messages, I am a beginner with CFX...

Best regards,

Tensi