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MarkBiz83 December 26, 2010 10:40

general VOF setting
I have to do a classic study with the VOF on a hull of a ship, the problem is that I searched the internet possible FLUENT settings to my problem but I could not find an acceptable solution.

In particular, I active
Stady - VOF - implicit scheme - open channel flow - implicit body force

I set the volume control: (BC)
- two in faces (one for water, one for air), both with "pressure inlet" and option of open channel active (I impose the velocity of the fluid and the height of free surface)
- one output face, "pressure outlet" with the same impostations of inlet faces (open channel active and gauge pressure = 0)

I make a patch to impose initial conditions:
- initial velocity of fluid
- volume fraction of volume control and I impose rate = 1 to the proportion of the volume representing the water.

From a first view of the problem seems that I have everything correctly set up. But when I start the simulation, even if I arrive at the convergence of solution, the velocity of the fluid are completely different from my case study!

For exemple if the initialization was set at 10 m/s, after the convergence I find that the speed is at 5-6 m/s. It's not what I want to study, I want to simulate a channel with the velocity of the fluid determined by me!!

Please someone tell me what is wrong (except my english :))!

Many thanks in advance

zhaopeng December 28, 2010 09:16

I think you need not to define water and air inlet separately with this method.

MarkBiz83 December 28, 2010 12:22

no, this setting is correct, i read this in ansys's manual, i have another problem but I don't know what it is!
Perhaps the Fr number in too high.....
thanck a lot too!

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