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gitsnedbutzi August 19, 2010 09:10

measure flow through a hole in cfd post

I have a problem in CFD post.
Inside my fluid domain, I have a structure which has two holes for an opening.
I want to compare the fluid flow of those two holes.
I could use an expression to evaluate the mass flow.
However I dont have a location (plane, etc.) for those two holes.
Is it possible to select create a location for the hole?

The geometry looks something like this:


---  ----  ---

Thanks a lot!

ghorrocks August 19, 2010 18:26

Yes. It is a bit clunky but it can be done. You need to define a surface to integrate the flow over somehow - options include planes with limits, contour surfaces or I think you can import XYZ points as user surfaces. Then use the function calculator to get the flow rate (or whatever you want) across the surface.

gitsnedbutzi August 20, 2010 05:19

thanks, that helped. now i can calculate the massflow with an expression, but how could i calculate the heat flow?

ghorrocks August 22, 2010 18:29

use the function calculator to get the heat flux integrated over the surface.

gitsnedbutzi August 23, 2010 03:20

but it says that the variable is not available on the plane. is it in general only available on boundaries and interfaces, as it says in the help or is there a chance to use it on planes?

ghorrocks August 23, 2010 07:36

Sorry, I meant general heat flux, not the variable heat flux which is only at the walls. Integrate the enthalpy.

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