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Calculation of thermodynamic and physical properties using NeqSim

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Even Solbraa edited this page Dec 16, 2021 · 10 revisions

Examples of reading thermodynamic and physical properties can be seen in the example.

To calculate thermodynamic properties of a fluid, the init() method needs to be called first:

fluid.init(3);

The number in the method depends on the type of property that should be calculated. 1 - density and fugacity, 2- all properties from 1. + temperature and pressure derivatives + enthalpy, entropy, etc. 3. Composition derivatives of thermodynamic properties (eg. composition derivatives of fugacity coefficients)

To calculate transport properties use the method:

fluid.initPhysicalProperties();

Reading fluid properties (sum of all phases):

fluid.getNumberOfPhases(); // Mix Number of Phases fluid.getPressure("Pa"); // Mix Pressure [Pa] fluid.getTemperature("K"); // Mix Temperature [K] fluid.getMoleFractionsSum() * 100; // Mix Mole Percent 1.0 / fluid.getDensity("mol/m3"); // Mix Molar Volume [m3/mol] fluid.getDensity("kg/m3"); // Mix Density [kg/m3] fluid.getZ(); // Mix Z Factor fluid.getMolarMass() * 1000; // Mix Molecular Weight [g/mol] fluid.getEnthalpy()/fluid.getNumberOfMoles(); // Mix Enthalpy [J/mol] fluid.getEnthalpy("J/mol"); fluid.getEntropy()/fluid.getNumberOfMoles(); // Mix Entropy [J/molK] fluid.getEntropy("J/molK"); fluid.getCp("J/molK"); // Mix Heat Capacity-Cp [J/molK] fluid.getCv("J/molK");// Mix Heat Capacity-Cv [J/molK] fluid.Cp()/fluid.getCv();// Mix Kappa (Cp/Cv) fluid.getKappa();// Mix Kappa (Cp/Cv)

Reading phase properties:

fluid.getMoleFraction(phaseNumber) * 100; // Phase Mole Percent fluid.getWtFraction(phaseNumber) * 100; // Phase Weight Percent 1.0 / fluid.getPhase(phaseNumber).getDensity("mol/m3"); // Phase Molar Volume [m3/mol] fluid.getCorrectedVolumeFraction(phaseNumber) * 100;// Phase Volume Percent fluid.getPhase(phaseNumber).getDensity("kg/m3"); // Phase Density [kg/m3] fluid.getPhase(phaseNumber).getZ(); // Phase Z Factor fluid.getPhase(phaseNumber).getMolarMass() * 1000; // Phase Molecular Weight [g/mol] fluidProperties[t][k++] = fluid.getPhase(phaseNumber).getEnthalpy() / >fluid.getPhase(phaseNumber).getNumberOfMolesInPhase(); // Phase Enthalpy [J/mol] fluid.getPhase(phaseNumber).getEnthalpy("J/mol"); // Phase Enthalpy [J/mol] fluid.getPhase(phaseNumber).getEntropy() / fluid.getPhase(phaseNumber).getNumberOfMolesInPhase(); // Phase Entropy [J/molK] fluid.getPhase(phaseNumber).getEntropy("J/molK"); // Phase Entropy [J/molK] fluid.getPhase(phaseNumber).getCp() / fluid.getPhase(phaseNumber).getNumberOfMolesInPhase(); // Phase Heat Capacity-Cp [J/molK] fluid.getPhase(phaseNumber).getCp("J/molK"); // Phase Heat Capacity-Cp [J/molK] fluid.getPhase(phaseNumber).getCv() / fluid.getPhase(phaseNumber).getNumberOfMolesInPhase(); // Phase Heat Capacity-Cv [J/molK] fluid.getPhase(phaseNumber).getCv("J/molK"); // Phase Heat Capacity-Cv [J/molK] fluid.getPhase(phaseNumber).getCp() / fluid.getPhase(phaseNumber).getCv(); // Phase Kappa (Cp/Cv) fluid.getPhase(phaseNumber).getKappa(); // Phase Kappa (Cp/Cv) fluid.getPhase(phaseNumber).getJouleThomsonCoefficient() / 1e5; // Phase JT Coefficient [K/Pa] fluid.getPhase(phaseNumber).getSoundSpeed(); // Phase Velocity of Sound [m/s] fluid.getPhase(phaseNumber).getPhysicalProperties().getViscosity();// Phase Viscosity [Pa s] fluid.getPhase(phaseNumber).getViscosity("kg/msec");// Phase Viscosity [Pa s] or [kg/msec] fluid.getPhase(phaseNumber).getPhysicalProperties().getConductivity(); // Phase Thermal Conductivity [W/mK] fluid.getPhase(phaseNumber).getConductivity("W/mK"); // Phase Thermal Conductivity [W/mK]

Viscosity models

Examples from https://colab.research.google.com/github/EvenSol/NeqSim-Colab/blob/master/notebooks/thermodynamics/ViscosityOfFluids.ipynb#scrollTo=PzWrasHBWB3X

method = "friction theory" fluid1.getPhase('gas').getPhysicalProperties().setViscosityModel(method) fluid1.initProperties() print("gas viscosity ", fluid1.getViscosity('cP'), " cP ", " metod: ", method)

method = "LBC" fluid1.getPhase('gas').getPhysicalProperties().setViscosityModel(method) fluid1.initProperties() print("gas viscosity ", fluid1.getViscosity('cP'), " cP ", " metod: ", method)

method = "PFCT" fluid1.getPhase('gas').getPhysicalProperties().setViscosityModel(method) fluid1.initProperties() print("gas viscosity ", fluid1.getViscosity('cP'), " cP ", " metod: ", method)

method = "PFCT-Heavy-Oil" fluid1.getPhase('gas').getPhysicalProperties().setViscosityModel(method) fluid1.initProperties() print("gas viscosity ", fluid1.getViscosity('cP'), " cP ", " metod: ", method)

method = "polynom" fluid1.getPhase('gas').getPhysicalProperties().setViscosityModel(method) fluid1.initProperties() print("gas viscosity ", fluid1.getViscosity('cP'), " cP ", " metod: ", method)

Thermal Conductivity Models

See https://colab.research.google.com/github/EvenSol/NeqSim-Colab/blob/master/notebooks/thermodynamics/ThermalConductivityOfFluids.ipynb

fluid1 = fluid('srk') fluid1.addComponent('methane', 0.5) fluid1.addComponent('ethane', 0.5) fluid1.setTemperature(25.0, 'C') fluid1.setPressure(42.0, 'bara') TPflash(fluid1)

method = "PFCT" fluid1.getPhase('gas').getPhysicalProperties().setConductivityModel(method) fluid1.initProperties() print("gas thermal conductivity ", fluid1.getThermalConductivity('W/mK'), " W/mK ", " metod: ", method)

method = "polynom" fluid1.getPhase('gas').getPhysicalProperties().setConductivityModel(method) fluid1.initProperties() print("gas thermal conductivity ", fluid1.getThermalConductivity('W/mK'), " W/mK ", " metod: ", method)

method = "Chung" fluid1.getPhase('gas').getPhysicalProperties().setConductivityModel(method) fluid1.initProperties() print("gas thermal conductivity ", fluid1.getThermalConductivity('W/mK'), " W/mK ", " metod: ", method)

Interfacial Tension

See https://colab.research.google.com/github/EvenSol/NeqSim-Colab/blob/master/notebooks/thermodynamics/interfacialtension.ipynb

fluid1 = fluid('srk') fluid1.addComponent('methane', 0.5) fluid1.addComponent('n-heptane', 0.5) fluid1.setTemperature(25.0, 'C') fluid1.setPressure(10.0, 'bara') fluid1.setMixingRule('classic') TPflash(fluid1)

method = "Parachor" fluid1.getInterphaseProperties().setInterfacialTensionModel("gas", "oil", method); fluid1.initProperties() print("Interfacial tension ", fluid1.getInterfacialTension('gas', 'oil'), " N/m ", " metod: ", method)

method = "Linear Gradient Theory" fluid1.getInterphaseProperties().setInterfacialTensionModel("gas", "oil", method); fluid1.initProperties() print("Interfacial tension ", fluid1.getInterfacialTension('gas', 'oil'), " N/m ", " metod: ", method)

method = "Simple Gradient Theory" fluid1.getInterphaseProperties().setInterfacialTensionModel("gas", "oil", method); fluid1.initProperties() print("Interfacial tension ", fluid1.getInterfacialTension('gas', 'oil'), " N/m ", " metod: ", method)

Adsorption models

See https://colab.research.google.com/github/EvenSol/NeqSim-Colab/blob/master/notebooks/thermodynamics/Interfacialadsorption.ipynb

Diffusion Coefficients

See: https://colab.research.google.com/github/EvenSol/NeqSim-Colab/blob/master/notebooks/thermodynamics/diffusioncoefficients.ipynb

NeqSim - a Java library for oil and gas process calculations

  1. Getting started with NeqSim and GitHub
  2. Getting started as a NeqSim developer
  3. The NeqSim parameter database
  4. Example of setting up a fluid and running simple flash calculations
  5. Select thermodynamic model and mixing rule
  6. Flash calculations and phase envelope calculations using NeqSim
  7. Calculation of thermodynamic and physical properties using NeqSim
  8. Oil Characterization in NeqSim
  9. Aqueous fluids and NeqSim
  10. Electrolytes and NeqSim
  11. Process Calculations in NeqSim
  1. Adding a thermodynamic model in NeqSim
  2. Adding a viscosity model in NeqSim
  3. Adding an unit operation in NeqSim
  4. How to make a NeqSim API
  5. Create native image using GraalVM
  6. Profiling calculations
  7. Dynamic process simulations
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