## Fluids

Topics relate to Fluent, CFX, Turbogrid and more

#### purpose of youngs modulus and possion ratio in ansys fluent

• rohan_btech19
Subscriber

What is the purpose of Youngs modulus and poison ratio during ansys fluent material defining?

and secondly ,can I directly evaluate the pressure change due to a change in wall thickness of a solid pipe without performing FSI? (its a non thermal problem and pressure based solver )

• Rob
Ansys Employee

It for the intrinsic FSI function. There's a limited structural code in Fluent.

If the wall thickness changes without effecting the ID then why would the pressure change?

• rohan_btech19
Subscriber

If I assign solid material to its wall thickness without changing ID and then can I evaluate the pressure generated on its wall/will pressure change if wall thickness changes as you mentioned it have intrinsic fsi and limited structural code

• Rob
Ansys Employee

The wall thickness changing will effect the wall stiffness which with intrinsic FSI may then alter the ID. You'd probably need a very high pressure for you to see much change though.

• rohan_btech19
Subscriber

thanks for the information

may I the approximately in what orders the pressure should be high

• Rob
Ansys Employee

It depends on the pipe: a balloon only needs a low pressure to distort, not sure I'd fancy trying to blow up a steel bag!  There's almost certainly a stress/strain/bendy calculation in your course notes or on the Learning section here.

It's more usual to calculate or specify the pressure you have, do some sums (on paper/spreadsheet) to find out what won't distort and order the next tube thickness up from that.

• rohan_btech19
Subscriber

Thanks a lot, Rob,

It would be a great help if you can provide any material or weblink where I can find mathematical relation between solid domain and liquid domain (or where I can see the code of intrinsic FSI)?

kind regards

• Rob
Ansys Employee

Here  https://ansyshelp.ansys.com/account/Secured?returnurl=/Views/Secured/corp/v231/en/flu_ug/flu_ug_models_fsi.html

• rohan_btech19
Subscriber

Thanks for sharing Rob but unfortunately I am not able to access the link due to some login issue.

So can you please share a screenshot or share through some other method from where I can access it easily.

• Rob
Ansys Employee

Click on Help in the solver, than paste the link into that browser. The solver includes the cookie/token/biscuit that bypasses the log in.