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| - | Hi
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| - | I'm working on oil distribution analysis. My flow model consists on small passages (diam. 4 mm)
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| - | and I have to run a steady-state analysis with a commercial Code. Re number is about 12000. Flow enters
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| - | from a circular tube (Inlet b.cond.) and exit from two ducts (Pressure b. cond)
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| - | 1) I cannot use k-eps high-Re with wall function because I should use a 0.8-1 mm cell at wall
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| - | in order to have correct y+ (30-100).
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| - | 2) Then I tried to use both two layer models and k-eps low-Re/Hybrid Wall Function with a proper fine
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| - | mesh at wall (15 layers with y+ less than 1).
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| - | I do not know if the second way is correct or not. I can only say that by using the last two turbulence models
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| - | 3) I found some strange values for heat transfer coefficients at wall, about 24000-30000 W/m2 K while proper
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| - | values should be 4000-5000 W/m2 K
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| - | Could anyone tell me why I found so high heat trasfer coefficients and if low-Re models are correct or not
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| - | for such calculations?
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| - | Thanks in advance.
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| - | Massimo
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Latest revision as of 16:26, 20 December 2005
