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 Pete February 8, 2006 14:29

Very simple moving mesh

Hi there,

I need to create a very simple moving mesh to test out the function. What I would like to do is create a 2D axisymmetric laminar pipe flow mesh with two halves, and allow the mesh to deform over time, much like this:

http://img215.imageshack.us/img215/9202/problem9yn.jpg

Then I would like to compare the results from this to that of a non-deforming mesh. Can this simple moving mesh be created without the use of a UDF or do I need to write one? Perhaps there is a simpler way for me to obtain a moving mesh?

Any help/tips/comments would be greatly appreciated!

Pete

 mAx February 9, 2006 01:27

Re: Very simple moving mesh

hi, yes it is very simple (in your case) you just have to work with layering. So your mesh has to be with quad. You can just write a profile with your velocity. In the dynamic mesh panel, enable layering, then define your moving wall with rigid body, add the motion description with your profile.Then you just need to define 2 stationnary walls (from which cell layers will be added or suppressed. That's all Hope it helps mAx

 Pete February 9, 2006 13:23

Re: Very simple moving mesh

Hey mAx, thanks very much for the reply, it was very useful. With regard to the profile, what variables do I need to include to move the profile from one place to another.

Presumably I need to have some time steps (e.g from 1 to 10) and then the position - like this?:

((wall.8 transient 10 1) (time 1 2 3 4 5 6 7 8 9 10 ) (x-coordinate 1.9949999 1.95 1.90 1.85 1.80 1.75 1.70 1.65 1.60 1.55 ) )

I tried this and it doesn't seem to work....

 Pete February 9, 2006 14:33

Re: Very simple moving mesh

Actually I have just got it working! Thanks very much for your help, I wouldn't have been able to figure it out otherwise.

For those wanting to use my solution, my profile file is as follows (This assumes only one profile is moving relative to another):

((velocity_inlet.11 transient 10 1) (time 1 2 3 4 5 6 7 8 9 10 ) (x 0 -0.1 -0.2 -0.3 -0.4 -0.5 -0.6 -0.7 -0.8 -0.9 ) )

 mAx February 10, 2006 01:12

Re: Very simple moving mesh