Cavity volume as an input (rather than pressure)

[biofriendly]

Dear all,

I would like to model a closed cavity with incompressible hydrostatic fluid inside.

The cavity is deformed in the interaction between the internal fluid being which is increased in volume by adding new water (at a known rate) and the external elastic interactions. The pressure is being measured. I know how to model the problem using fluid elements, using *static, and cavity interaction, defining pressure as an input. However, I would like to have volume as a control parameter.

I looked around in the manuals but I havent found any straightforward so far. Any ideas guiding me to the right direction?

Thanks a lot in advance...

A

 

[FEA way]

There is an option to specify additional volume in a fluid cavity, maybe this could give you the form of control that you are looking for.

 

[biofriendly]

Thanks. Any chance you would remember the keyword? I tried fluid expansion but that didnt work.

 

[FEA way]

This option can be specified using added volume parameter for *Fluid cavity keyword. So it should look like this:

*Fluid cavity, name=…, ref node=…, behavior=…, added volume=magnitude_of_additional_volume
…

 

[biofriendly]

I see that it is still not supported in CAE (which is not a problem but why I missed it). so much. Helped a lot!

 

[biofriendly]

One more question: I added the keyword. Nothing happens regardless of the value I assign to it. I removed the cavity pressure BC. Additionally, how can I assign to it an amplitude (added volume rate)?

 

[FEA way]

Check the documentation chapter "Analysis --> Analysis Techniques --> Special-Purpose Techniques --> Surface-based fluid modeling --> Fluid cavity definition", it describes these options in detail. However, amplitudes are not supported in this case.