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modelling evaporation-condensation in closed system

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Old   October 12, 2013, 11:07
Default modelling evaporation-condensation in closed system
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ali mondegari
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hi
i am modelling a two-phase flow for water liquid and vapor in steady state in a closed system . it contains evaporation and condensation. is using VOF right for this case ? i fill half of the system with water in initialization but after some iteration total mass of system decrease significantly and continuity equation never converge . what's the reason ?
please help me
thanks
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Old   February 6, 2014, 08:17
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amine
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I try to simulate the same problem. I use a mixture model with tree phase (air, liquid, vapor). After few iterations I have this message: # Divergence detected in AMG solver. I had try to change the under relaxation value, but is diverge as well.
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Old   February 20, 2014, 12:08
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amine
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Hi
You must use a transient solver for a good convergence.
I used a coupled scheme with flow number of 50I used 0.001 s time step to have stable convergence
Good luck
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Old   April 25, 2014, 00:09
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Xiaobing Zhang
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Hi guys,
I'm doing similar problems right now. So did you use Fluent evaporation-condensation model to do the calculation or wrote your own udf for the simulation?
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Old   April 25, 2014, 00:20
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Xiaobing Zhang
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Hi guys,

In my view, if you use VOF to do this simulation, you should write UDF by yourself for the eva-conden process. But if you turn to Mixture model, you can use the written model.
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