Problems using a formula to determine inlet velocity

Ashh · October 6, 2013, 17:25

Hi all, first post!

I'm modelling a square duct with a 90 degree bend. With a uniform inlet velocity of 10m/s everything solves fine.

However when I introduce the condition of the inlet velocity being based around a formula (2*Ub*(1-(x^2+y^2)/(0.5*D)^2), with Ub and D defined in expressions, the solver crashes with "Return code 1" & "Non-zero error code 2".

The inlet is centered around the origin with the z axis pointing into the inlet.

Any ideas as to what is wrong?

Cheers
Ash

AshwaniAssam · October 7, 2013, 00:08

Which solver are you using? And the OS. It can be problem of compiler. Like we use gcc, g++ compiler and it crashes mostly with segmentation violation.

Ashh · October 7, 2013, 20:37

Thanks for the reply AshwaniAssam.

I was using ANSYS CFX. The problem turned out to be something glitchy in the geometry as when I loaded a Solidworks IGES version of the geometry into the analysis it worked.

I'm still unsure why the ANSYS geometry solved with a uniform inlet velocity and not with a profiled velocity but it's working now.

AshwaniAssam · October 7, 2013, 23:23

You can see the following thread. In general these error codes will have some information somewhere on net.

http://www.cfd-online.com/Forums/cfx...-code-1-a.html

October 6, 2013, 17:25	Problems using a formula to determine inlet velocity	#1
Ashh New Member Ash Join Date: Oct 2013 Posts: 3 Rep Power: 12	Hi all, first post! I'm modelling a square duct with a 90 degree bend. With a uniform inlet velocity of 10m/s everything solves fine. However when I introduce the condition of the inlet velocity being based around a formula (2Ub(1-(x^2+y^2)/(0.5*D)^2), with Ub and D defined in expressions, the solver crashes with "Return code 1" & "Non-zero error code 2". The inlet is centered around the origin with the z axis pointing into the inlet. Any ideas as to what is wrong? Cheers Ash

October 7, 2013, 23:23	Reply	#4
AshwaniAssam Senior Member Ashwani Join Date: Sep 2013 Location: Hyderabad Posts: 154 Rep Power: 12	You can see the following thread. In general these error codes will have some information somewhere on net. http://www.cfd-online.com/Forums/cfx...-code-1-a.html

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October 7, 2013, 00:08		#2
AshwaniAssam Senior Member Ashwani Join Date: Sep 2013 Location: Hyderabad Posts: 154 Rep Power: 12	Which solver are you using? And the OS. It can be problem of compiler. Like we use gcc, g++ compiler and it crashes mostly with segmentation violation.

October 7, 2013, 20:37		#3
Ashh New Member Ash Join Date: Oct 2013 Posts: 3 Rep Power: 12	Thanks for the reply AshwaniAssam. I was using ANSYS CFX. The problem turned out to be something glitchy in the geometry as when I loaded a Solidworks IGES version of the geometry into the analysis it worked. I'm still unsure why the ANSYS geometry solved with a uniform inlet velocity and not with a profiled velocity but it's working now.