Residual Results Issue

elcheapo · March 9, 2016, 08:37

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

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.

March 21, 2016, 22:31		#2
LeeTao New Member LeeTao Join Date: Nov 2015 Posts: 3 Rep Power: 10	Hello, elcheapo Have you tried to decrease the time step? sometimes it can help. Leetao Nabuchadresar likes this.

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March 27, 2016, 23:14		#4
Nabuchadresar Member André Luiz Moura Silva Moreira Join Date: Apr 2015 Location: Brazil Posts: 40 Rep Power: 10	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.