Learning Forum

[Marius Carrier]

Hello,

I have a geometry with round symmetrical features that includes multiple inlets. The goal was to utilize symmetry by grouping the left and right sides together and applying a symmetry boundary condition. However, I'm still experiencing flows in a manner that is not desired (picture below). What steps should I take to ensure that the flow exits from the right side and enters from the left side (and vice versa)?

Thank you for your help.

Regards.

 

 

[Federico Alzamora Previtali]

Hello Marius, 

it is difficult to depict what your flow should look like from your picture. Can you share a screenshot of your domain?

[Marius Carrier]

I'm not allowed to show you much more, but could you please clarify what you mean by domain?

I have created a sketch in OneNote to illustrate my point. Instead of the flow bouncing off the wall (Case 1), I want it to enter from the left wall (Case 2). Is that explanation better?

[Federico Alzamora Previtali]

By domain, I mean your simulation domain or your model/geometry. It is still unclear to me what this should look like.

Are you sure it is symmetry that you are looking for? Or is this an outlet? 

[Rob]

Domain is the generic term for whatever you're modelling. So in this case, the CFD mesh/geometry. 

Just a note, anything modelled using Student MUST be for your learning, and is therefore not confidential. Anything modelled with Research level licences is (technically) supposed to be published at some point. For commercial type or very confidential projects you should be using the Commercial level licences. Please discuss with your supervisor to make sure you're not accidentally outside the terms. If you're at all unsure please contact Ansys. 

[Marius Carrier]

Yes I'm sure I'm using the correct liscens. If you would tell me what you need I'm happy to provide you the info.

Do you undestand the problem I'm discribing?

[Marius Carrier]

I can't show you the whole domain. What exactly are you looking for?

Right now, it is treating the left wall of the geometry as a wall, despite implementing the symmetry condition on the walls. I want the airflow to perceive the left boundary not as a wall, but as a portal to the right wall. It is not an outlet because this would imply that the flow is exiting rather than entering from the right side.

[Federico Alzamora Previtali]

I believe you are describing a periodic boundary.

[Rob]

To add, symmetry is essentially a mirror surface so everything will "bounce off" it. As Federico suggests I think a periodic is what you're after: read 

https://ansyshelp.ansys.com/account/Secured?returnurl=/Views/Secured/corp/v231/en/flu_ug/flu_ug_bcs_sec_bound_cond.html

https://ansyshelp.ansys.com/account/Secured?returnurl=/Views/Secured/corp/v231/en/flu_ug/flu_ug_sec_periodic_hxfer.html