[GregM]

I did not find a thread directly linked to the topic below but i might have missed it, so apologies if this has been hashed out before.

I'm a long time fluent user\part time cfx user but at my new workplace I have been unsuccessful at convincing the powers that be that the cost of those packages is worth it.

That being said we are going to try using openfoam for the immediate simulation needs (which is exciting as I generally enjoy expanding my skillset) that being said, let me lay out the problem I have and hopefully someone can point me to either an appropriate tutorial or at least give me some confidence that taking the time to learn openfoam as related to this problem will not be wasted.

Fluid type: Incompressible, turbulent flow
Basically, I have two regions, one moving, one not. The upstream region is a flow straightener with N passages. The downstream region is a vaned impeller with M vanes where M != N surrounded by a drum that rotates at the same speed as the impeller. On the outside of the drum is a stationary asymmetric wall that is "sealed" using a labyrinth seal between the drum and the wall.

I need to investigate flow over the tips of the impeller vanes between the ID of the moving drum and the tips of the impeller vanes and the flow through the labyrinth seal on the OD of the drum.

I would set this problem up in fluent by making a wedge shaped section with cyclic-periodic boundary conditions for the flow straightener, a different wedge with cyclic - periodic bc's for the impeller-drum region along with setting the reference frame for the downstream region to move at a fixed angular velocity. The interface between the two regions would be a mixing plane method. Velocity inlet to the start of the flow straightener, & pressure outlet from the impeller to round out the non-wall BC's.

Can something similar be done in openfoam? Is there a decent tutorial or tutorial set that covers this type of problem?

thanks
Greg

[skyinventorbt]

Try tutorials. If I am correct, I remember one tutorial must be there for rotating & moving mesh for the problem of your kind.

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KANNAN B T

[fumiya]

Hi,

You might want to try

MRF(Multiple Reference Frame) model

• incompressible/simpleFoam/mixerVessel2D

Arbitrary Mesh Interface (AMI)

• incompressible/pimpleDyMFoam/mixerVesselAMI2D
• incompressible/pimpleDyMFoam/oscillatingInletACMI2D

Hope this helps,
Fumiya

[kalle]

Hi,

You might want to look into the foam-extend-3.0 version of the code. Håkan Nilsson of Chalmers have had some PhD students working on rotating machinery. See for instance

http://www.tfd.chalmers.se/~hani/pdf...T_IAHR2009.pdf

http://wikki.gridcore.se/foam-extend...xtend-3-0-jeju

Kalle

[GregM]

I will look into both of those. I just got the computer set up with openfoam and foam-extend, so I will start with those and go from there.

thanks
Greg

[Tushar@cfd]

For your need, I think the best test case will be "ERCOFTAC" in OpenFOAM.

For more information, refer to the link:

http://openfoamwiki.net/index.php/Si...vaned_diffuser

The above link is self-explanatory.

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Best Luck!