residuals keeping decreasing in linear way

solefire · August 12, 2009, 04:04

Dear CFD lovers,

I am simulating ventilation in empty room. (STEADY STATE) 0.6 million nodes
I used very fine boundary layer close to the wall, the distance from the first node to the wall is 0.001 with 12 rows for boundary layer! While far away from the wall, I am using relatively coarse mesh , with successive growing ratio 1.05 double sided (because there is exit ).

Before running I made an estimation for residuals value which is around 1e-12. And what is happening now is residuals are keeping decreasing in linear way , obviously it is not converged when I check velocity contour in cross section (because this room is totally symmetric, cubic).

By the way the whole thing is based on 1e-11. I am using k-epsilon model, RNG, with initial turbulence intensity 1%.

Is there any one who can give me some hint or explanation . I appreciate all what you will do!

Best regards

C.J

solefire · August 12, 2009, 04:12

By the way the whole thing is based on 1e-11. Thanks!

August 12, 2009, 04:04	residuals keeping decreasing in linear way	#1
solefire Member CJ Join Date: Jun 2009 Posts: 34 Rep Power: 16	Dear CFD lovers, I am simulating ventilation in empty room. (STEADY STATE) 0.6 million nodes I used very fine boundary layer close to the wall, the distance from the first node to the wall is 0.001 with 12 rows for boundary layer! While far away from the wall, I am using relatively coarse mesh , with successive growing ratio 1.05 double sided (because there is exit ). Before running I made an estimation for residuals value which is around 1e-12. And what is happening now is residuals are keeping decreasing in linear way , obviously it is not converged when I check velocity contour in cross section (because this room is totally symmetric, cubic). By the way the whole thing is based on 1e-11. I am using k-epsilon model, RNG, with initial turbulence intensity 1%. Is there any one who can give me some hint or explanation . I appreciate all what you will do! Best regards C.J Last edited by solefire; August 12, 2009 at 05:06.

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August 12, 2009, 04:12		#2
solefire Member CJ Join Date: Jun 2009 Posts: 34 Rep Power: 16	By the way the whole thing is based on 1e-11. Thanks!