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Old   January 27, 2009, 12:51
Default I'm running a 2D axial symmetr
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Nat Trask
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I'm running a 2D axial symmetric case in rasInterFoam right now of a coaxial fuel injector. I'm getting seemingly random spurts of k and epsilon that shoot out of the symmetry axis and then die down. They form about 8 diameters downstream of the nozzle. Does anyone have experience with something like this? My boundary conditions are correct and the simulation runs fine with turbulence off. I'm using kEpsilon and wedge boundary conditions on the two planes.

Thanks,
Nat
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Old   January 28, 2009, 00:24
Default I had strange results on an ax
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Kirk Jarvis
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I had strange results on an axial symmetrical case where the symmetrical axis patch type was set to symmetryPlane. Without particle injection the case seamed to give reasonable results. Once the particle were injected all the particles collected on the symmetry axis.

Changing the axis plane patch to empty cleared up the issues. It was not clear in any of the documentation (I have access to) that the axis of symmetry should have an empty patch type.

I know it is a stab in the dark but thought it might help.

Kirk
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Old   February 15, 2009, 14:09
Default Hi foamers! I'm simulating a
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hamdi
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Hi foamers!
I'm simulating a case of a injercteur (axisymmetric) of a Pelton turbine with a flow twophasique water + air with the RANS turbulence model,
in other words, can I find a solver that treats the flow inside the nozzle and the flow twophasic outside of this injector at the same time, if there is someone who can help me for this,
I would be very grateful.
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Old   February 15, 2009, 20:05
Default Take a look at rasInterFoam an
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Nat Trask
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Take a look at rasInterFoam and the dambreak tutorial.

On a related note, I noticed that the solver uses turbulence models that assume a constant density (clearly not applicable for two-phase flow). Does anyone have insight toward why that may be?

-Nat
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Old   February 16, 2009, 05:40
Default thank you Nak ! I investigate
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hamdi
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thank you Nak !
I investigated the rasInterFoam tuturail, in fact it speaks about twophasique at 0 velocity, in addition it is not axisymmetric.
I do'nt know if there is something that speak about the flow inside of a cylindrical duct and jet at the same time with the RANS model.

Thank you again
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Old   February 16, 2009, 11:17
Default You will want to use the rasIn
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Nat Trask
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You will want to use the rasInterFoam solver but create your own case. Take a look at the user guide to see how to change boundary conditions. lesInterFoam has a 2d axial symmetric mesh that you can take a look at.
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