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semo July 5, 2013 11:51

porous jump problem
 
Hello,

I am trying to model a simple flow in a duct. I have number of turns in the duct system and I placed a filter which is modeled as a porous jump. I followed Fluent manual to assign C2 and alpha values which should give me a high pressure drop (2" H2O), however, when I check inlet/outlet pressure differences I have a very low pressure drop (0.1" H2O). This makes me think porous jump is not active?

Is there any other setting other than changing the boundary condition from interior to porous jump?

Please help, thanks in advance...

semo July 8, 2013 09:10

anybody? please share if you have any ideas. thank you...

delaneyluke July 10, 2013 12:35

What I do is start with the calculated values of C2 and alpha and then gradually increase them to achieve the required pressure drop.

The difference could be the difference in velocities or flow rates between testing the filter and placing the filter in your system

Regards
Luke

Tanjina July 10, 2013 17:27

1 Attachment(s)
hello all. How can you calculate alpha value ? I am trying to model a very simple geometry a porous pipe submerged in water. I modeled in 2D. I just put an arbitrary value for alpha i.e. 0.3. But my model looks like the attached figure.

And how can I measure the pressure difference between inlet and outlet ?

Please let me know if anyone can help.


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