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[ANSYS Meshing] Periodic boundary condition failure

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Old   May 5, 2022, 15:21
Default Periodic boundary condition failure
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Sakun
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Hi,

I created my naca65-009 blade using ICEM and top , bottom have a distance of 134.

after scaling down to mm in the fluent , i tried to set up periodic conditions to the top and bottom but none of the methods worked. tried both manual and automatic detection.

even if i gave 0.134 to the manual detection , it did not captured.

can someone help me on this
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Old   May 6, 2022, 04:46
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Don't use fluent for this. CFX is made for rotating equipment.
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Old   May 6, 2022, 07:00
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so does it mean, it is impossible in fluent ?

the thing is i have never used cfx
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Old   May 6, 2022, 13:24
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Quote:
Originally Posted by Sakun View Post
so does it mean, it is impossible in fluent ?

the thing is i have never used cfx
No, don't worry, ignore the previous comment. Almost all features of CFX have been translated to Fluent. Both product are owned by ANSYS. Fluent has mesh motion, frame motion, mixing plane and all other things needed for your simulation.

Fluent also has a Turbo-workflow specially designed for turbo application.

It's a very old idea that CFX is for turbo and fluent isn't, usually said by people who are not up to date with CFD development, things have changed substantially. Also, try using Turbo grid or Fluent Meshing for mesh generation. These are the new and updated packages, ICEM is not really being used much in the industry.
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Old   May 6, 2022, 13:25
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Quote:
Originally Posted by Sakun View Post
Hi,

I created my naca65-009 blade using ICEM and top , bottom have a distance of 134.

after scaling down to mm in the fluent , i tried to set up periodic conditions to the top and bottom but none of the methods worked. tried both manual and automatic detection.

even if i gave 0.134 to the manual detection , it did not captured.

can someone help me on this
Also, ask this question in Fluent forum.
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Old   May 11, 2022, 13:20
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I think Fluent is horrible when it comes to transient analysis. It is not even possible to only save pressure and velocities field every time step. The Data File Quantities list only allows me to select all variables. Very inefficient and it is eating my hard disk.
CFX is forgiven to bad elements. Fluent crashes immedietely.
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Old   May 11, 2022, 14:20
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Quote:
Originally Posted by Gert-Jan View Post
I think Fluent is horrible when it comes to transient analysis. It is not even possible to only save pressure and velocities field every time step. The Data File Quantities list only allows me to select all variables. Very inefficient and it is eating my hard disk.
CFX is forgiven to bad elements. Fluent crashes immedietely.
Last I checked, you can do exactly that, select which variable you want to save(pressure, velocity, density etc.) and when, i.e iteration, time step or flow time. You have a built in post-processing as well so no need to save and move files, it can be done in the same application.

As far as issues with accuracy and convergence are concerned, there isn't much difference between CFX and Fluent(although they are essentially different solvers), both are excellent, depends on mesh quality. Fluent has it's own mesher that does poly and poly-hexcore meshing using parallel computing, so less element overall and much faster mesh time. Again, both are owned by the same company, they are equally good, although they are focusing more on developing Fluent as it is their main product.
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Old   May 9, 2023, 22:28
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One potential solution to fix this issue is to ensure that your mesh is properly aligned and centered around the blade. If your mesh is not properly aligned, the periodic boundary condition setup may fail. contexto
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fluent, icem, icem 2d blocking, periodic bc, periodic boundary fluent

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