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HIgh pressure zone near the outlet?

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Old   May 24, 2013, 05:43
Default HIgh pressure zone near the outlet?
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To finetune the settings for my case (which is a valve) using rhoSimplecFoam, I firstly made a simple tube simulation with similar domain dimensions.

It is a pressure driven flow, the pressures at the inlet and outlet are fixed but the velocities are unkown. Thus I set the inlet pressure and outlet pressure with fixed values.

left side, inlet, high pressure.
right side, outlet, low pressure.

For the inlet U it is a pressureInletVelocity bc, but no matter how I changed the outlet bc, for example, pressureInletOutletVelocity, inletOutlet or zeroGradient, after the pressure gradients builds up, there is a large jump near the outlet, which could be seen in the attached figures.

I guess it is a boundary condition setting problem. But I think the options I tried are the most feasible ones, no other options I could think of.

Any suggestions?

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Old   May 27, 2013, 03:34
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hi
What occurs in jump area if you decrease the outlet pressure?
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Old   May 29, 2013, 23:01
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Quote:
Originally Posted by immortality View Post
hi
What occurs in jump area if you decrease the outlet pressure?
Immortality,

The outlet pressure should be fixed at this value based on the application requirement. But I will make one case with decreased pressure to spot the problem.
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Old   June 1, 2013, 06:03
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i have a problem like you.
Please let me know how you solved the problem.
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