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Search took 0.00 seconds. Search: Posts Made By: ghorrocks
Forum: CFX September 19, 2012, 18:37
Replies: 29
Views: 4,907
Posted By ghorrocks
Yes, you will need a source term coefficient to...

Yes, you will need a source term coefficient to get things like this to converge. But even with that implemented this still might be tricky to get convergence - give it a go and see if it works.
Forum: CFX September 17, 2012, 18:45
Replies: 29
Views: 4,907
Posted By ghorrocks
Your comments are pretty much what I expected....

Your comments are pretty much what I expected. The Source term approach is the bets bets of my suggestions and your directional loss idea might work as well.

For the source term approach you need...
Forum: CFX September 13, 2012, 23:39
Replies: 29
Views: 4,907
Posted By ghorrocks
Some ideas of specifying volume fraction: *...

Some ideas of specifying volume fraction:
* Specify a volume fraction initial condition, and use the "solve vf" expert parameter to turn solution of the VF equation off. This is a bit dodgy as the...
Forum: CFX September 13, 2012, 22:43
Replies: 29
Views: 4,907
Posted By ghorrocks
You can prescribe the motion and measure the...

You can prescribe the motion and measure the force in immersed solids.

You can describe much more complex motions with immersed solids, and the mesh is a simple hex mesh covering the region so...
Forum: CFX September 13, 2012, 21:16
Replies: 29
Views: 4,907
Posted By ghorrocks
Sounds fun. For your model I would consider using...

Sounds fun. For your model I would consider using an immersed body to do the motion and run it single phase. This would be much easier if you do not want to consider free surface deformation.

But...
Forum: CFX September 13, 2012, 20:25
Replies: 29
Views: 4,907
Posted By ghorrocks
What are you trying to learn with this model?...

What are you trying to learn with this model? What is the output from this simulation?
Forum: CFX September 13, 2012, 19:14
Replies: 29
Views: 4,907
Posted By ghorrocks
If you know where the free surface is and it does...

If you know where the free surface is and it does not move then why model the air at all? put the domain boundary on the free surface and make it an opening with a pressure of 0 Pa on the interface....
Forum: CFX September 8, 2012, 07:22
Replies: 29
Views: 4,907
Posted By ghorrocks
What free surface parameters did I test? All of...

What free surface parameters did I test? All of them - I systematically worked through all of them and worked out what each one did. I used a few simple benchmarks such as a drop on a surface,...
Forum: CFX September 6, 2012, 18:59
Replies: 29
Views: 4,907
Posted By ghorrocks
A finer mesh will probably result in more...

A finer mesh will probably result in more wobbles, not less.

These wobbles are very hard to reduce, especially with surface tension models. Your best bet is to improve mesh quality at the...
Forum: CFX August 2, 2012, 20:20
Replies: 29
Views: 4,907
Posted By ghorrocks
The choice between inhomo vs homo is more about...

The choice between inhomo vs homo is more about what size bubbles you want to model. If they are big enough that the free surface model can resolve them, then go homogeneous. If you are going to get...
Forum: CFX August 1, 2012, 22:02
Replies: 29
Views: 4,907
Posted By ghorrocks
* You are using the inhomogeneous multi phase...

* You are using the inhomogeneous multi phase model. Do you anticipate mixed air/water (eg fine bubble or foam)? The homogeneous model is much simpler and is more appropriate if a distinct interface...
Forum: CFX August 1, 2012, 19:52
Replies: 29
Views: 4,907
Posted By ghorrocks
Please post the CCL. Do you include surface...

Please post the CCL.

Do you include surface tension?

When I did free surface modelling some time ago I set up a little test case (ie a small, simple mesh) where I tested the effects of all the...
Forum: CFX August 1, 2012, 19:31
Replies: 29
Views: 4,907
Posted By ghorrocks
Then attach the CCL. It is a small text file. ...

Then attach the CCL. It is a small text file.

Can you also do a drawing of what is going on? Where is the water level, what motion does the plate have?
Forum: CFX August 1, 2012, 18:47
Replies: 29
Views: 4,907
Posted By ghorrocks
Can you post some images and the output file of a...

Can you post some images and the output file of a demonstration?
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