Visualize high residual Cell in Fluent

Daniel_Khazaei · October 22, 2014, 07:48

Hello guys

I am modeling a pulsatile flow through an artery with Ansys Fluent. However I have a problem in convergence after a few time step.

The same case converges well when I use Newtonian fluid model for the blood, but switching to any non-Newtonian model causes a convergence problem after a few time step.

I am using pressure-based coupled solver with the default settings. I have already tried reducing courant number and under relaxation factors with no luck. I have also tried different P-V coupling schemes, but the exact same behavior occurs after a couple of time steps.

Is there any way to visualize which cells are causing the problem? So I can try and fix the mesh.

The current mesh quality metrics are as follow:

- maximum skewness : 0.6
- maximum aspect ratio : 36
- minimum orthogonal quality: 0.5

Thanks in advance

Daniel_Khazaei · October 25, 2014, 16:04

anyone?

Fabio88 · July 24, 2016, 11:23

Hi,
I was also looking to a way to visualize the cells which are causing bad residuals.
Did you find any method ?

Thanks,
Fabio

October 22, 2014, 07:48	Visualize high residual Cell in Fluent	#1
Daniel_Khazaei Senior Member Daniel Join Date: Mar 2013 Location: Noshahr, Iran Posts: 348 Rep Power: 21	Hello guys I am modeling a pulsatile flow through an artery with Ansys Fluent. However I have a problem in convergence after a few time step. The same case converges well when I use Newtonian fluid model for the blood, but switching to any non-Newtonian model causes a convergence problem after a few time step. I am using pressure-based coupled solver with the default settings. I have already tried reducing courant number and under relaxation factors with no luck. I have also tried different P-V coupling schemes, but the exact same behavior occurs after a couple of time steps. Is there any way to visualize which cells are causing the problem? So I can try and fix the mesh. The current mesh quality metrics are as follow: - maximum skewness : 0.6 - maximum aspect ratio : 36 - minimum orthogonal quality: 0.5 Thanks in advance

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October 25, 2014, 16:04		#2
Daniel_Khazaei Senior Member Daniel Join Date: Mar 2013 Location: Noshahr, Iran Posts: 348 Rep Power: 21	anyone?

July 24, 2016, 11:23		#3
Fabio88 Member Fabio Malizia Join Date: May 2010 Location: Leuven (Belgium) Posts: 51 Rep Power: 16	Hi, I was also looking to a way to visualize the cells which are causing bad residuals. Did you find any method ? Thanks, Fabio