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How to define 2 grids to move the inner object?

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Old   April 12, 2011, 09:09
Default How to define 2 grids to move the inner object?
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Hans Johans
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problem description:

I want to simulate a case with a moving object.
Can somebody help me and give some ideas for the principal approach.



It should be similar to this project
http://www.youtube.com/watch?v=S-p0uau9nGA

I would solve it in this way:

1. Design the grid of the big rectangle (with a rectangle-shaped hole in the middle)


2. Design grid of the small rectangle with the object in the middle
3. Write a UDF for movement
4. Use the fluent funktion to reshape the grid during the simulation. (dynamic meshing)


My questions:

1. Do I have to divide the 2 rectangles in the mesher or in the geometry-builder?
When I use the Designmodeler, draw the 2 rectangle and the object, click then on "surface from sketches", the space between inner rectangle and circle is empty. And I don't know how to avoid that. Some Ideas?

2. Are there any faults in my plan?
3. Any suggestions to improve it?

Last edited by lepetitmort; April 12, 2011 at 12:21.
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Old   April 13, 2011, 13:05
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Simon Pereira
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These are separate overlapping grids? I have never actually solved one of these, but I would guess that you probably need to mesh them separately, not as a single model. Then overlap the mesh models in the solver.
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Old   April 16, 2011, 09:01
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The trick is
1. to make TWO sketches.
2. splitface
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Old   April 16, 2011, 12:05
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That will get you your nested box structure, but won't allow the one mesh to fall thru the other... Or do you mean to morph th outer box?

Sorry, I thought you planned for overlapping grids.
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Old   June 30, 2011, 12:38
Default mesh morphing
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I think that the problem can be faced using the mesh morphing tool RBF Morph (www.rbf-morph.com).

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Old   July 1, 2011, 16:58
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I have looked at a variety of morphing tools and none are more powerful or better integrated into Fluent than RBF-Morph...

Simon
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