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Magma January 8, 2013 00:52

Problems With understanding domain Interface
2 Attachment(s)
As suggested by ghorrocks, I have used all the necessary means to tackle my problem.
I have been working with a problem in Particle Tracking, using Cyclone, and I am using CFX as the software. I have simulated the problem using solid domain and the result was as expected but it does not help to work out with embedded geometry.
Can any one help me to understand the domain interface side 1 and 2, I will post the picture file and if necessary send 3D model and and pre file.
I have attached a zip file with model in parasolid extension.Attachment 18034

Attachment 18035
I know somebody is out there who is willing to help.
Cheers!! :)

monkey1 January 8, 2013 05:09

If I understand you correctly you want an interface between the inner geometry and the "hull" or wall???
When you define a domain interface side 1 and 2 just specify the the surface of the interface assigned as part of the inner geometry and the one assigned to your solid domain.
Or what was your specific question about side 1 and 2????

ghorrocks January 8, 2013 05:12

Domain interfaces are associated with.... domain interfaces. That is a bit of a statement of the obvious I guess....

Domain interfaces are used to connect different domains (or even the same domain). This means they are generated in the CFX-Pre stage of pre-processing, so your parasolid will not have them. You need to finish the geometry and meshing first.

But I note your solid model looks like a thin shell, as if that was the model of the metal shell of the body. You need to convert that to a solid of the fluid domain for simulation.

Magma January 8, 2013 05:39

Domain Interface
Guys thanks, as you said.. domain interface is domain interface. So in my case it must be used to connect the lid and the wall so the inner section of the lid at inlet and outlet must be the interface.
I have been suggested to use the solid domain, but what about the embedded geometry? That will not be displayed, or is there any way to show that too. The file/model is not an assembly, it is a part file, this makes hard to show something embedded inside. If anyone is willing to help me, I will send him the model, created with solidworks. I just need one chance to understand domain interface, in my model.. may be someone could help me by setting that in "pre".
Please help this fool with Domain interface!!! I got ignorant in this case.:(

ghorrocks January 8, 2013 18:15

What are you trying to model?

The only reason you would model the outside shell is if heat transfer inside the shell is important. If it is not important then you can ignore it and then you have no need for domain interfaces.

Magma January 8, 2013 23:37

Domain Interface-Reason for Modeling outer shell

Inside the model there is a pipe, and if I model it solid, i don't think that the pipe can be seen in pre(may be I am wrong). I understand that solid body does not need interface, I have simulated this problem with solid body. But in that case the geometry inside the body is not seen.
No I don't need heat transfer study in this case.
How can see the geometry inside the body, when the body is solid. Is there any option to do that, it would be a lot easier, if so.
Thank you for your reply.

ghorrocks January 9, 2013 05:47

If you are not modelling heat transfer then do not model any solid body. Just cut that bit out of the domain block and it will become a wall boundary. Then you do not need interfaces. Have a look at the tutorial examples - I think the workbench tutorials show this sort of operation.

jrl4444 January 9, 2013 13:03

SolidWorks Combine to make Domain from part
4 Attachment(s)
Well to view it I would provide Section views .... I pulled the part up and yes like said here before you have a part mold only. Looks like you have closed over the inlets and outlets. Seems you have worked with FloXpress or some other build in CFD package with SolidWorks. That is how they operate, the solver builds the domain from the closed in part cavity you provide. That leaves you with little to no control over the mesh. CFX most likely will not produce your domain for you from just a shell but most SolidWorks packages have a couple ways to easily build the Domain solid. One is using Mold Tool bar that has a Create cavity command. The other more straight forward method is under COMBINE BODIES, during this operation you can choose to SUBTRACT one body from another. To produce the Domain Solid you need. I am thinking from what I can tell is that you do not need an interface you only need identify a few bounties to produce openings / inlet / outlet.

It took me 30 seconds to produce the part you need, where do I send it?

Magma January 10, 2013 00:17

Domain Interface-Mission succesful
Thank you for help, I actually tried to workout with the model you sent and it worked :p. Thank you very much.
I concluded that the problem was with my modeling/Geometry.
I was lagged with this problem since 3 months, very much thanks to you and all who replied and suggested!!!
Thanks again.!!:):):)

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