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-   -   Residual Results Issue (https://www.cfd-online.com/Forums/star-ccm/167812-residual-results-issue.html)

elcheapo March 9, 2016 08:37

Residual Results Issue
 
2 Attachment(s)
Hi guys,

I have a problem with the output results for Residual.

This is compared to the original tutorial results. My simulation had some geometry changes.

Steps were done trying to improve the situation. This includes
1. Changing the max inner iteration and stopping criteria
2. Changing the monitor>normalised option from Auto to Off

Any inputs from gurus here on solving the issue? The 'Water' readings seemed to be deviating upwards quite a lot.

LeeTao March 21, 2016 22:31

Hello, elcheapo

Have you tried to decrease the time step? sometimes it can help.

Leetao

elcheapo March 26, 2016 13:59

Quote:

Originally Posted by LeeTao (Post 590947)
Hello, elcheapo

Have you tried to decrease the time step? sometimes it can help.

Leetao

Hi Leetao, i somehow managed to observe it to be caused by the overset surrounding thr object. Hence having the entire overset lowered such that it comes into contact with water surface totally solved the issue.

Nabuchadresar March 27, 2016 23:14

Maybe you may change the under relaxation factor (pressure and velocity) or improve the mesh.

Decrease the time-step is a option too.


I'm a new student on CFD, but I could try this.


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