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[EvenSol]

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[GrandZangoule]

Hello all, I have a couple of questions:

1. How do I get the mole fraction of each component in the different phases?
2. Does the package calculate Dew/Bubble point Temperatures and pressures?

[EvenSol]

Hi.
1.
How do I get the mole fraction of each component in the different phases?

#Mole fraction of a component in total fluid
fluid1.getComponent('methane').getz()

#Get mole fraction of a phase (moles in phase/total number of moles)
fluid1.getPhase('gas').getMoleFraction()

#Mole fraction of component in a phase of type gas, oil or aqueous:
fluid1.getPhase('gas').getComponent('methane').getx()
fluid1.getPhase('oil').getComponent('methane').getx()
fluid1.getPhase('aqueous').getComponent('methane').getx()

#Mole fraction of component in phase number 0..n - where order is from lightest to heaviest:
fluid1.getPhase(0).getComponent('methane').getx()

#and mole fraction for first added component( component number 0) in th lightest phase:
fluid1.getPhase(0).getComponent(0).getx()

#molar composition
fluid1.getMolarComposition()

You can see some examples here:
https://colab.research.google.com/github/EvenSol/NeqSim-Colab/blob/master/notebooks/emptytemplate.ipynb

2. Does the package calculate Dew/Bubble point Temperatures and pressures?
   Yes. You use the dew point temperature and dew point pressure methods in https://github.com/equinor/neqsim/blob/master/src/main/java/neqsim/thermodynamicOperations/ThermodynamicOperations.java

[GrandZangoule]

Thank you very much for your quick response. Your answer to question #1 was exactly what I needed.
For question #2, I could not find the function to use to calculate or obtain the Bubble or Dew point. I tried a few functions but had errors. Please help with the correct function calls.

Thanks again.

[EvenSol]

These examples might be usefull:
https://github.com/EvenSol/NeqSim-Colab/blob/master/notebooks/gasquality/hydrocarbon_dew_point_of_natural_gas.ipynb.

You can run the following script in Python:

# Calculation of dew and bubble points

import neqsim
from neqsim.thermo.thermoTools import dewt, bubt,bubp, dewp, fluid
import matplotlib.pyplot as plt

fluid0_HC = fluid('srk')
fluid0_HC.addComponent('methane',0.7)
fluid0_HC.addComponent('ethane',0.1)
fluid0_HC.addComponent('propane',0.1)
fluid0_HC.addComponent('n-butane',0.1)
fluid0_HC.setMixingRule("classic")

fluid0_HC.setPressure(10.0, 'bara')
fluid0_HC.setTemperature(0.0, 'C')

dewtemperature = dewt(fluid0_HC)
print('dew point temperature ', fluid0_HC.getTemperature('K'), ' K', ' pressure ', fluid0_HC.getPressure('bara'), ' bara')

#set inital guess
fluid0_HC.setTemperature(-140.0, 'C')
bubtemperature = bubt(fluid0_HC)
print('bubble point temperature ', fluid0_HC.getTemperature('K'), ' K', fluid0_HC.getPressure('bara'), ' bara')

#set inital guess
fluid0_HC.setTemperature(-50.0, 'C')
fluid0_HC.setPressure(30.0, 'bara')
bubpressure =bubp(fluid0_HC)
print('bubble point pressure ', fluid0_HC.getPressure('bara'), ' bara ',  fluid0_HC.getTemperature('K'), ' K')

#set inital guess
fluid0_HC.setTemperature(275.0, 'K')
fluid0_HC.setPressure(30.0, 'bara')
dewpressure =dewp(fluid0_HC)
print('dew point pressure ', fluid0_HC.getPressure('bara'), ' bara ',  fluid0_HC.getTemperature('K'), ' K')

from neqsim.neqsimpython import jNeqSim
thermoOps = jNeqSim.thermodynamicOperations.ThermodynamicOperations(fluid0_HC)
thermoOps.calcPTphaseEnvelope()

plt.plot(list(thermoOps.getOperation().get("dewT")),list(thermoOps.getOperation().get("dewP")), label="dew point")
plt.plot(list(thermoOps.getOperation().get("bubT")),list(thermoOps.getOperation().get("bubP")), label="bubble point")
plt.title('PT envelope')
plt.xlabel('Temperature [K]')
plt.ylabel('Pressure [bar]')
plt.legend()
plt.show()

Output:

dew point temperature 274.8507677589821 K pressure 10.0 bara
bubble point temperature 155.42940315451594 K 10.0 bara
bubble point pressure 65.1502714869753 bara 223.14999999999998 K
dew point pressure 10.06055839453803 bara 275.0 K

[GrandZangoule]

Worked perfectly. Thank you very much. Your routines are awesome. I have some ideas I'm working on and will like to collaborate with your team on the near future.

Thanks again.

[GrandZangoule]

How do I suppress this and any other messages?
error could not calculate

[EvenSol]

The message is printed in the thermoTools.py that you import and use. One option can be to call neqsim directly and not via thermoTools.

The other option will be to disable logging (however this is not available in the current release).
import logging
logging.disable(logging.CRITICAL)

You can test it from github:
pip install git+https://github.com/equinor/neqsim-python.git