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doum April 3, 2007 15:12

Hi! I am kind of new to openf
I am kind of new to openfoam, but it looks like this is what I need!
I am a master student, working in natural risks. I am trying to model a "submarine rockfall". In few words : A big rock (more than 1m of diameter) fall from a submarine cliff and travel in the water. It may bounce on the cliff, roll, slide, or have a "freefall" behavior.
I would like to model the simplest case : a sphere that may have only freefall behavior or bouncing behavior.
Some of you seems experts in CFD modeling. What is the simplest way to do what I want to do? (or if no simplest way, what should I do!)
Thanks a lot!

P.S. Sorry for my english! My first language is french!

eugene April 4, 2007 05:59

By far the easiest method in O
By far the easiest method in OpemFOAM would be to model the rock as a very very viscous fluid using the inteface capturing VOF method. I'm not sure how accurate this would be since fluids generally don't support elastic deformation (i.e. no bouncing), but I guess it would be a good starting point.

After this I would suggest you contract an experienced OpenFOAM developer to add the additional stress terms to the transport equations. Or keep learning and do so yourself!

I vaguely recall a project about baking cookies and residual stresses from ~5 years ago. Perhaps someone still has that code.

doum April 4, 2007 09:09

Thanks a lot! This seems to b
Thanks a lot!
This seems to be a good starting point!
In fact, I don't think I will have to introduce elastic deformations on the rock. For the "collisions", I will try to use what we call restitution coefficients (ratio between in and out velocity). When the mass will be very close to the cliff, there will be an apparent contact force, but the block won't deform...

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