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3D simulation: Extract 2D integrated solution values along a path

I have solved a 3D problem with the RF module, electromagnetic waves (emw), which gives me a nice 3-dimensional electric field distribution.

Now I have a problem with the evaluation, maybe someone of you can help me.
The geometry is sth. extruded from a 2D geometry. In 2D there is a rectangle (R), centered to x,y=0, which in 3D into the z dimension becomes extruded to a long (prolate) rectangular block. It is kind of a waveguide.

What I need: The power flow into z direction (P), integrated in a plane, which is the rectangle (R) over the z coordinate.
I now already tried, defining me a Results-> Datasets->CutLine 3D.
Is this the right approach? Is it possible to define there a 2D integration which I can extract as a scalar along the z (1D) extension?
I have also already included a "line" object in my geometry, central (x,y=0), as I hoped, maybe, I could at least get scalar values along this line. But in principle I want to do this aforementioned 2D integration before going along the line.

To be honest, at this point I am now a bit at a loss.

Has anyone of you already done this?
I guess, if it is then in this discussion forum as an answer, maybe it could be also a good help for others ;-)

Best regards!

Arian

6 Replies Last Post Jun 28, 2011, 4:04 PM EDT
Posted: 7 years ago Jan 5, 2011, 1:46 AM EST
Hi

in 4.1 you can define a cut plane ("artificial" interpolated boundary in the results data set) and then integrate over this plane. Often I cut my geometry to have an interiour boundary that I can select and define some probe or integration operator thereon and use them in the postprocessing

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Good luck
Ivar
Hi in 4.1 you can define a cut plane ("artificial" interpolated boundary in the results data set) and then integrate over this plane. Often I cut my geometry to have an interiour boundary that I can select and define some probe or integration operator thereon and use them in the postprocessing -- Good luck Ivar

Posted: 6 years ago Jun 6, 2011, 4:30 PM EDT
Hi Ivar,

I'm using Comsol 4.1 to solve liquid flow and heat transfer problem in channels. What I need is to evaluate integration or average value on a cross-section plane. I know I can define a "cut plane" to do this. But is there any method to define the boundary of the plane, since on the same plane I've other structures which are not of interest.

I wonder if "parameterized surface" would be a possible solution. But I could not find sufficient instruction information concerning that topic in the help file.

Thank you.
Cheng
Hi Ivar, I'm using Comsol 4.1 to solve liquid flow and heat transfer problem in channels. What I need is to evaluate integration or average value on a cross-section plane. I know I can define a "cut plane" to do this. But is there any method to define the boundary of the plane, since on the same plane I've other structures which are not of interest. I wonder if "parameterized surface" would be a possible solution. But I could not find sufficient instruction information concerning that topic in the help file. Thank you. Cheng

Posted: 6 years ago Jun 7, 2011, 6:38 AM EDT
Hi

but cannt you cut then your geoemtry such that you have a boundary you can integrate over ?

--
Good luck
Ivar
Hi but cannt you cut then your geoemtry such that you have a boundary you can integrate over ? -- Good luck Ivar

Posted: 6 years ago Jun 7, 2011, 1:35 PM EDT
Hi,

I used to cut my geometry in the drawing step and it works. But is it possible to cut it in the postprocessing step? I don't want to reconstruct the model and solve it again and again for postprocessing purpose.

Thank you.
Cheng
Hi, I used to cut my geometry in the drawing step and it works. But is it possible to cut it in the postprocessing step? I don't want to reconstruct the model and solve it again and again for postprocessing purpose. Thank you. Cheng

Jeff Hiller COMSOL Employee
Posted: 6 years ago Jun 7, 2011, 1:46 PM EDT
You could use a cut plane dataset combined with an integration expression that involves a boolean. Something like T*(dom==1) if you want to integrate T and only integrate on the intersection of your cutplane with domain 1.
You could use a cut plane dataset combined with an integration expression that involves a boolean. Something like T*(dom==1) if you want to integrate T and only integrate on the intersection of your cutplane with domain 1.

Posted: 6 years ago Jun 28, 2011, 4:04 PM EDT
Hello, Cheng.
Have you managed to solve this issue? Could you help me, please? I am in the same situation now.
Thank you
Hello, Cheng. Have you managed to solve this issue? Could you help me, please? I am in the same situation now. Thank you

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