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Old   January 30, 2013, 09:51
Default Air-water jets
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José María Carrillo
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Hello,

I am modeling a 100 meters free discharge air-water jet. I chose:
-SST turbulence model
-Multiphase: Homogeneous model

The water volume fractions and pressures at stagnation point where a little high when I used 0.5m mesh size. Results increased using a mesh size of 0.4m and there are huge using a 0.3 m mesh size.

I have using a mesh size of 0.30m and the jet has a diameter of 1.5 meters, with a falling length of 100 m.

For the fluid pair model, Interphase transfer, in the 0.3 m mesh size I probed different setting:
- Standard.
- Free surface with different maximum length scale for area density (1.0; 0.5; 0.02; 0.002 m)
- Mixture model:50mm

However, the air volume fraction entrain in the jet is less than 0.2, when this must be very high, while pressures at stagnation point are enormous.

Can you give me some advices?
Best Regards

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Old   January 30, 2013, 17:54
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Glenn Horrocks
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