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difference between ‘volume’ and ‘volume of finite volumes’ in cfx

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Old   October 8, 2018, 13:57
Default difference between ‘volume’ and ‘volume of finite volumes’ in cfx
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Hi, there,

When I export the data from .res in CFX-post, I have noticed that there is discrepancy between ‘volume’ and ‘volume of finite volumes’ in cfx. But I didn’t find the definitions of these two variables in the open documents. May I know why these two variables are different?
More specifically, I’d like to know when the volumetric quantities are used, which kind of volume are used?
When the volume integral are used which kind of volume are used?

Thank you very much!
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Old   October 8, 2018, 14:37
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the answer is "depends".

If you are doing an integral where the elemental volume refers to the control volume, i.e

integral over the volume (integrand) dV = Sum of (integrand at node * Volume of control volume)

However, if the elemental volume refers to the element,

integral over the volume (integrand) dV = Sum of (integrand at the element * volume of the element)

For certain

Global Sum (volume elements) = Global Sum (control volume volumes)

It depends on how you want to evaluate the specific integral.

Control volume volume = Sum of (sector volumes around a node)

Hope the above helps
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Old   October 9, 2018, 14:14
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Thank you, Opaque!
Do you mean: in CFX-Post
'volume' is the elemental volume;
'volume of finite volumes' is the Sum of (sector volumes around a node)?
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