[Yorkshire2019]

Dear all,

I have modelled a slice of a turbine and intend to model the entire turbine using cyclic symmetry. My results don't appear to show the flow of fluid across periodic/cyclic boundaries. Also, I do not know how to view the full scaled model of my turbine, is there a way to reflect the cyclic segments of my model?

I have performed the following stages:

1. Assigned cyclic symmetry regions on the high and low boundary (left and right internal segment faces). Referencing a cylindrical coordinate system at the origin.

2. Assigned 'match control' mesh at the high and low boundary faces.

3. Entered fluent and assigned periodicity at the high and low boundaries using 'grid/modify-zones/make-periodic' command.

The response in the command window was successful and formed one periodic boundary condition.

Have I missed any stages?

Using: ANSYS FLuent

[LuckyTran]

You'll only get the results of the slice because that's what you are solving.

If you want to see the full 360°, you have to do some post-processing. Google some youtube videos on periodic repeats and look for this part in the manual.

Originally Posted by Yorkshire2019

Also, I do not know how to view the full scaled model of my turbine, is there a way to reflect the cyclic segments of my model?

Your model is not full scale, it's a slice. In the future if you want the full scale model, then simulate the full scale model. There's a difference between reality and wishful thinking. Okay I get there are obvious reasons why you would want to simulate a slice instead of the full sector, but that is not an excuse to manipulate the language into something that it is not. =)

[Yorkshire2019]

Originally Posted by LuckyTran

You'll only get the results of the slice because that's what you are solving.

If you want to see the full 360°, you have to do some post-processing. Google some youtube videos on periodic repeats and look for this part in the manual.



Your model is not full scale, it's a slice. In the future if you want the full scale model, then simulate the full scale model. There's a difference between reality and wishful thinking. Okay I get there are obvious reasons why you would want to simulate a slice instead of the full sector, but that is not an excuse to manipulate the language into something that it is not. =)

Thank you for your response! Full 360deg post-processing makes sense. Despite it working before, I'm having issues creating the periodic boundary condition (Error: Failed to make zones periodic. Error Object: #f). I've tried checking my cylindrical axis, interchanged high/low boundaries and mesh uniformity to no avail.

Why am I using symmetry? I save an 11th of the computational expense if I can succeed in applying cyclic symmetry, which will be significant by the time I simulate rotational multi-phase flow.

I've been trying to establish the difference between cyclic and period symmetry, they may both be suitable in my case - perhaps you're able to clarify?

[LuckyTran]

You need to take a deep breath.


There are only two boundary conditions in Fluent. Periodic and symmetry. Symmetry is not for you. All the other fancy words you use are not Fluent but for the mesher (or perhaps even completely made up by you).

Originally Posted by Yorkshire2019

Why am I using symmetry? I save an 11th of the computational expense if I can succeed in applying cyclic symmetry, which will be significant by the time I simulate rotational multi-phase flow.

????? I didn't say anything about symmetry. Are you having a conversation with someone else?

[Yorkshire2019]

I hadn't distinguished these things between Fluent and Mesher, but clearly you aren't familiar with them. The periodic symmetry is referring to your slice or full sector comments.

[LuckyTran]

Yes clearly I'm not familiar with them.

[AlexLi_AeroEn]

Hi, Yorkshire.

Recently I've been working with cyclically periodic symmetry using Ansys Meshing as mesher and Fluent as Solver. I accidentally obtained expected mesh by following steps:

1. Inserted 'Pre-meshed Cyclic Regions' in Meshing, named face boundaries and coordinate system and gave the number of repeats.

2. Inserted 'Mesh Match' for two mentioned faces.

3. Generated Mesh and loaded it into Fluent, you should have an automatically coupled boundary naming something like 'periodic' with its type set as the only existing option 'periodic'.

Why accidentally? Because till now I failed to redo this process!!!
SAD and depressed. My version is 2019 R2.

[AlexLi_HIT_KHAI]

Originally Posted by AlexLi_AeroEn

Hi, Yorkshire.

Recently I've been working with cyclically periodic symmetry using Ansys Meshing as mesher and Fluent as Solver. I accidentally obtained expected mesh by following steps:

1. Inserted 'Pre-meshed Cyclic Regions' in Meshing, named face boundaries and coordinate system and gave the number of repeats.

2. Inserted 'Mesh Match' for two mentioned faces.

3. Generated Mesh and loaded it into Fluent, you should have an automatically coupled boundary naming something like 'periodic' with its type set as the only existing option 'periodic'.

Why accidentally? Because till now I failed to redo this process!!!
SAD and depressed. My version is 2019 R2.

Here I attached a link which may help you solve this problem
FLUENT Periodic Boundary Condition SOLVED + TUTORIAL