## Integration over a specific, bounded plane

Moderators: davetaflin, salter, steve, jprenaud, straton, Chris Idso

Newbie
Posts: 3
Joined: Wed Apr 25, 2012 5:23 am
Location: US

### Integration over a specific, bounded plane

I need to take an area weighted average of temperature over a specific square-shaped plane. I have the coordinates of the 4 vertexes of this square. However I don't know how to set this up in the 'Perform Integration' window.

Where can I input these coordinates?

Can anybody help?

salter
Moderator
Posts: 188
Joined: Thu Dec 21, 2006 10:57 am
Location: NASA Langley Research Center
Contact:

### Re: Integration over a specific, bounded plane

If the square is not part of the data set, you will need to create a new grid, ordered or finite element, that can be used to transfer the data you have through interpolation. If you compute the area of the cells in the original data, you should interpolate that data onto the new grid as well. Then, you can perform an integration based on a variable, or if you like, compute your own weights from the interpolated, scale the temperature, then perform the integration in steps. But to select a specific range of data,

Conversely, if the data you have is square in geometry, you can provide the limit of I, J, and K to determine the region you want to integrate. But as it stands, you still have to compute area/volume to have it area weighted. The issue is that you cannot specify a region to integrate within the Tecplot software.
Steve...

Aerospace Research Engineer
Aerothermodynamics Branch
NASA Langley Research Center

Newbie
Posts: 3
Joined: Wed Apr 25, 2012 5:23 am
Location: US

### Re: Integration over a specific, bounded plane

I think I should have pointed out that the simulation was done in Fluent. In Fluent, it is possible to define an area by giving the coordinates of its four corners. However, in my simulation, this plane cuts through both a fluid and a solid region and I need the average temperature of the fluid only. Fluent doesn't have an option to 'deactivate' the solid region so to speak and includes it in the average. This is why I am trying to use Tecplot.

I read the section of the manual which explains about the I,J,K ranges but I'm afraid It didn't make much sense to me (I am very new to Tecplot). Assuming I,J and K represent the X,Y and Z axis, the range begins at 1 and can have a End value of 999999 (Mx). I have no idea what this means and I can't get Tecplot to show the region on the screen. The other question is: if the plane I need is perpendicular to say the Z-axis, the Z coordinates of all the points within this plane are the same; How is this setup in Tecplot?

Since the domain is complex, I really need to somehow translate coordinates to Tecplot.

salter
Moderator
Posts: 188
Joined: Thu Dec 21, 2006 10:57 am
Location: NASA Langley Research Center
Contact:

### Re: Integration over a specific, bounded plane

There is an addon in the Tecplot distribution called crsfez that can solve this for you. This addon will extract a cross-section of finite element data, where in this case the solid portion is blanked, into a new zone. You simply compile the addon, install it using the ADK manual information, generate your slice, blank the region of solid to not be included in the new zone, and create a new zone with this addon. Then do your averaging.
Steve...

Aerospace Research Engineer

Aerothermodynamics Branch

NASA Langley Research Center

Newbie
Posts: 3
Joined: Wed Apr 25, 2012 5:23 am
Location: US

### Re: Integration over a specific, bounded plane

That would be very helpful. I found this in another post:

##Tecplot has an addon called "crsfez" (Create Subzone of Finite Element Zone) which can create a subzone of a finite element zone. It can be activated by opening the tecplot.add file (a text file) in your Tecplot folder and finding the line that says:

Remove the "#" from the beginning of this line and then save and close the file. This will activate the addon, which will appear in your Tecplot/Tools menu.

This addon can create a subzone of the Finite element zone but it does it by extracting the portion of the Finite Element zone which is visible in the frame. So you need to adjust the frame, view, rotation, zoom etc to get the just the portion of the Finite Element zone you want to extract visible, and then run the addon.

Tecplot does not have any other way to extract a subzone of a finite element zone. Hope this works for you.##

It works and activates the sub-zone option in tools menu. I will let you know if I can do the averaging this way.

And by the way, thank your response!