Bulk averaged values on a surface plane other than the inlet or outlet planes..How??

nikesh · August 11, 2014, 22:13

Hi Boris,
Is it possible to obtain the bulk averaged values on a surface plane other than the inlet or outlet planes (lids)?
On my valve flow case, I want to obtain average pressure and velocity on a surface plane certain distance away from the center of the valve (on both the sides, upstream and downstream direction). And these planes are not the inlet or outlet planes. See the figure attached.
I'm still trying to figure it out, but in vain.
Any help appreciated.
Thanks
Nikesh.

Boris_M · August 14, 2014, 10:28

Hi Nikesh,

Yes, you simply add another lid at that position and use the component control to deactivate it for the flow. You can still apply goals on that or surface parameters and get the data you want to know. It is wise to increase the mesh in these lids as the fluid cells are often not that fine and would create a larger interpolation error.

By the way, did you send me your task via email already?

Regards,
Boris

nikesh · August 17, 2014, 07:02

Hi Boris,
This is the process that has to be applied before running the simulations, right? Is there a way to do so after simulations have been completed? I wish to check various parameters at different cross sections for the cases that have already been run and completed, but I have not created such lids at those positions.

Ah yes I had sent you an email few weeks ago, but I got an automated reply stating that you were on vacation. I could send it to you again after few updates in a couple of days if u r still up?

Thanks,
Nikesh.

Boris_M · August 18, 2014, 04:06

Hi Nikesh,
Well if you want to apply a finer mesh at these sections then you would need to mesh and run it again or at least continue to run it on the old results but you should be able to add these lids afterwards too and use them for the surface parameter feature. It should work as you only need a reference geometry but it might be a little inaccurate compared to a finer mesh version.

Ok, it seems that your email was accidently caught by the spam filter. Let me know when you sent it the next time so I can check if it got filtered again.

Boris

nikesh · August 18, 2014, 22:16

Boris,
But I can create lid only at the pipe opening, not somewhere in the middle of the pipe.....
Or perhaps there is another way??

Boris_M · August 19, 2014, 02:42

Yes, the create lids tool is supposed to be used for closing the goemetry for internal analysis and only works on planar surfaces where it recognises any holes in it but it won't work within a pipe at a certain location. For that you can either create one at the opening of the pipe and then move it to the location you want it to be via the CAD constraints or you can create some manually at these locations by putting a parallel plane to the opening to the location you want it to be and simply start with a sketch and extrude it.

Boris

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August 14, 2014, 10:28		#2
Boris_M Disabled Join Date: Jul 2009 Posts: 616 Rep Power: 24	Hi Nikesh, Yes, you simply add another lid at that position and use the component control to deactivate it for the flow. You can still apply goals on that or surface parameters and get the data you want to know. It is wise to increase the mesh in these lids as the fluid cells are often not that fine and would create a larger interpolation error. By the way, did you send me your task via email already? Regards, Boris

August 17, 2014, 07:02		#3
nikesh Member Nikesh Bhattarai Join Date: Nov 2011 Location: Sacheon, South Korea Posts: 82 Rep Power: 14	Hi Boris, This is the process that has to be applied before running the simulations, right? Is there a way to do so after simulations have been completed? I wish to check various parameters at different cross sections for the cases that have already been run and completed, but I have not created such lids at those positions. Ah yes I had sent you an email few weeks ago, but I got an automated reply stating that you were on vacation. I could send it to you again after few updates in a couple of days if u r still up? Thanks, Nikesh.

August 18, 2014, 04:06		#4
Boris_M Disabled Join Date: Jul 2009 Posts: 616 Rep Power: 24	Hi Nikesh, Well if you want to apply a finer mesh at these sections then you would need to mesh and run it again or at least continue to run it on the old results but you should be able to add these lids afterwards too and use them for the surface parameter feature. It should work as you only need a reference geometry but it might be a little inaccurate compared to a finer mesh version. Ok, it seems that your email was accidently caught by the spam filter. Let me know when you sent it the next time so I can check if it got filtered again. Boris

August 18, 2014, 22:16		#5
nikesh Member Nikesh Bhattarai Join Date: Nov 2011 Location: Sacheon, South Korea Posts: 82 Rep Power: 14	Boris, But I can create lid only at the pipe opening, not somewhere in the middle of the pipe..... Or perhaps there is another way??

August 19, 2014, 02:42		#6
Boris_M Disabled Join Date: Jul 2009 Posts: 616 Rep Power: 24	Yes, the create lids tool is supposed to be used for closing the goemetry for internal analysis and only works on planar surfaces where it recognises any holes in it but it won't work within a pipe at a certain location. For that you can either create one at the opening of the pipe and then move it to the location you want it to be via the CAD constraints or you can create some manually at these locations by putting a parallel plane to the opening to the location you want it to be and simply start with a sketch and extrude it. Boris