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Old   September 18, 2015, 18:35
Default Real gas NIST model problem
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Hello,

I am trying to run a simulation with real gas model from NIST using r134a as working fluid. When I try to initialisate or run the simulation I get the next message:

Primitive Error at Node 0: REFPROP_error (203) from function: tprho (density)
[TPRHO error 203] vapor iteration has not converged for T= 257.82 K, p =0.55582 MPA, rho (last guess) =0.39299 mol/L, x (mol frac) = 1.0000

I do not know how to make the Refprop function to converge. Anybody could give some advice about how to deal with it?

Best regards.
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Old   September 18, 2015, 19:20
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Lucky Tran
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Are you running a single phase or multiphase simulation? This can happen when you end up in a different phase (i.e. you should be in the supercritical phase or pure gas phase but somehow end up in the liquid phase).

If this is happening during initialization then check to make sure your initial conditions are consistent with the expected phase. If necessary, manually patch the pressure and temperature in affected zones/regions.
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Old   September 20, 2015, 08:16
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Hello,

I am running a single phase simulation. I am sure that the boundary conditions that I am setting are in single phase zone.

The problem that I am trying to run is a single-phase ejector and the boundary conditions are two pressure inlets and one pressure outlet, the rest are wall and symmetry.

The values of pressure and temperature in the error message do not seem to be in the single phase region but I do not know why it is trying to calculate this values since my boundary conditions are in single-phase.

Thank you for any further help.
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Old   September 20, 2015, 10:07
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Check your initial conditions.
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Old   September 20, 2015, 11:05
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Do you mean boundary conditions? or initial conditions? I have not set any initial conditions because I am running a steady simulation. And the boundary conditions I am pretty sure that are all of them in gas phase.

In the next link you can download my mesh and my script file if you want to have a look. https://www.dropbox.com/s/vivx4rkpjc...luent.zip?dl=0

Regards.
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Old   October 26, 2016, 01:33
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If anybody have solution to this problem, it will be helpful.

I am simulating a supersonic flow of supercritical CO2 through convergent divergent nozzle.

Inlet condition
Inlet : Pressure Inlet ;P0 = 95.7 bar
T0 = 315K
Real gas model : NIST
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Old   February 27, 2017, 06:18
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Lucia
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Hello,

How did you solve this issue?

I have a similar problem with a supersonic flow with R134a.

Best regards,
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