Learning Forum

[Kelsey O'Donnell]

I want to create a 3D bed of "mussels" that are tiny pumps and surround them in a fluid domain to simulate how their pumping impacts flow. The domain would be about 2 m by 0.5 m and the bed itself would be around 1 m by 0.5 m, the question I am partially trying to answer is how much of an impact the mussel pumping has on the hydrodynamics and mixing processes. Each mussel outlet would have a velocity of around 1-2 cm/s and I am looking at very slow (less than 5 cm/s) ambient flows. I am looking for guidance as to how I can do this, thank you!

[Rob]

Given the size of a mussel (are you looking at a "pile" or rope grown?) have a look at porous media and source terms. I'd really not want to work out the positions for around 1m3 of shellfish and then try and mesh them.

[Kelsey O'Donnell]

I am looking at an aggregation on a flat flume surface. Could you explain a bit more about what you mean look into porous media and source terms?

[Rob]

Thread pruning - Rob. 

[Kelsey O'Donnell]

Thank you, didn't mean to post twice but it didn't seem to be going through.

[Rob]

There were more than two threads.... 

If you're assuming the mussels are as above then single units may be OK. Think about the cell count you'd need to resolve each shell & opening, then multiply up to the whole domain. Porous media is covered in the User's Guide (click on Help in Fluent) as are source terms: both are cell zone conditions. 

[Kelsey O'Donnell]

Yes everytime I tried to post, it said the connection timed out and the posts were not appearing on my end so again I apologize for that. I understand the basics of porous media and source terms, I guess what I was asking what how you see me applying them to my simulation. Would the mussels be treated as porous media? 

[Rob]

No worries, the back end team have been doing stuff so it should be better now. 

It's an option for you to look at. In CFD we can solve most things, but if a mussel opening is 1-2mm across in a domain the size you're looking at the cell count may be rather high. There's also the transient effect - it's an in-out pumping rather than continuous.