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Christian May 21, 2003 09:39

UDF a at fixed z in space

I want to make a calculation in my udf in a 3d case at a fixed z value (ie. a plane at a fixed z).

Can anyone please assist me finding the correct macro?

Christian May 21, 2003 10:58

I guess that I am searching for the method to define to the macro where to loop over faces, cells....

It is not at a boundary. And I just want to report the values of the x-, y- and z-velocities.

mateus May 21, 2003 11:13

Re: Update

Im not shure if I understand. But if you want to report velocity at a certain poin in youd domain you can do it without UDF. Define a point (surface-point...) and turn on surface monitor (solve-monitors-surface) for velocity at that point...

best regards


Christian May 21, 2003 11:36

Re: Update

Yes I know. But I want to report the velocity at all cells in a plane defined by me.

mateus May 21, 2003 11:58

Re: Update

You can define a new plane with Surface-isosurface...grid



Christian May 22, 2003 03:25

Re: Update

Yes I know. What I don't know is how to link it to a udf in order to write values for all the faces in a specific surface. If that operation is possible to do directly in the surface command range (without a udf) I would like to know how. But as I see it the surface commands can only give average values or values in points defined by me. And that is not what I am looking for, but the face values.


mystic_cfd May 23, 2003 07:36

Re: UDF at fixed z in space
hi Christian

when you export values from a iso-surface/plane-surface/clip-surface, the values in the output are cell-centered values of the cells cut by your slice. this, i think, is the face values you are looking for? you can easily export this data to a number of different formats by just using the GUI/TUI.

if you are looking for the values of the faces of each cell, then you have to use a UDF, but it becomes more difficult to decide which cells belong to the z-plane you define.

good luck!

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