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How to define a fixed velocity for a given mass flow rate on inlet

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Old   April 12, 2013, 02:13
Exclamation How to define a fixed velocity for a given mass flow rate on inlet
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Qasim Ali
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hello,
I am simulating a turbulent flow through a vertical channel with some sort of blockage.
its mass flow rate at inlet is 0.3 kg/s
using mass flow rate = density* area* velocity for inlet i come up inlet velocity as 2.4 m/s
that is reasonable...
but when i step into fluent, i defined the mass flow rate exactly in vertical channel but inlet velocity is jumped up to 80m/s
how to fix this inlet velocity???
i am only defining the mass flow rate, rest i initialize the value from inlet that takes velocity in 80s, even if i keep it down but fianl form after iteration makes it deviate again.
in other words i want fixed velocity at inlet. help me out.
thankyou
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Old   April 12, 2013, 02:17
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I think your solution is not converged, that's why your velocity field and other variables are wrong.

Daniele
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Old   April 12, 2013, 17:24
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i tried different grids to check their independence, all yielded results in same pattern and it stops the results with comment solution is converged
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