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Different value of expression in CFD-Post and CFX-Solver

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Old   February 26, 2018, 09:37
Question Different value of expression in CFD-Post and CFX-Solver
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Hello,
I defined an expression in CFX-Pre:
areaAve(Temperature)@REGION:My_Selection

It's defined on a mesh region (named selection from Meshing), but there is no a boundary condition in CFX on this specified mesh region (it's a part of bigger region with boundary condition - wall).

I set up this expression to monitor in Output Control. Then I ran the simulation and it's finished with good convergence. I checked value of expression in CFX-Solver (left click on plot trace in last iteration) - it shows 90,3 C. Next, I opened CFD-Post and checked my expression. Its value in CFD-Post is different than in CFX-Solver (88,4 C). What is the reason of this difference? And which value is calculated properly?

Best regards,
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Old   February 26, 2018, 17:52
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In the solver expressions are evaluated using integration point values. In CFD-Post expressions are evaluated using nodal values. The nodal values are a coarser network and should be less accurate, so the solver expression is more accurate.

Is the mesh on this region relatively coarse? You only get significant differences when the integration point values are different to the nodal values, and that usually only occurs on coarse meshes.
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Old   February 28, 2018, 07:22
Default hi i have problem (Application Error in TurboGrid: ERROR Bladeset Count must be great
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hi i have problem (Application Error in TurboGrid: ERROR Bladeset Count must be great
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Old   March 1, 2018, 11:47
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Quote:
Originally Posted by omididay@yahoo.com View Post
hi i have problem (Application Error in TurboGrid: ERROR Bladeset Count must be great
Hello! I have problem too. Where can I buy some potatoes?
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