Class FugacityJacobian

java.lang.Object
neqsim.thermo.util.derivatives.FugacityJacobian
All Implemented Interfaces:
Serializable
public class FugacityJacobian extends Object implements Serializable
Container for Jacobian matrix of fugacity coefficients.

Stores derivatives of log fugacity coefficients (ln φ) for all components with respect to:

  • Temperature: ∂(ln φ_i)/∂T
  • Pressure: ∂(ln φ_i)/∂P
  • Composition: ∂(ln φ_i)/∂n_j (moles) or ∂(ln φ_i)/∂x_j (mole fractions)

These derivatives are fundamental for:

  • Flash calculation convergence (Newton methods)
  • Implicit differentiation through equilibrium
  • Stability analysis
Since:
3.0
Author:
ESOL
See Also:

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    private final String[]
    componentNames
    Component names.
    private final double[][]
    dlnPhidn
    Derivatives w.r.t. moles: ∂(ln φ_i)/∂n_j [1/mol].
    private final double[]
    dlnPhidP
    Derivatives w.r.t. pressure: ∂(ln φ_i)/∂P [1/bar].
    private final double[]
    dlnPhidT
    Derivatives w.r.t. temperature: ∂(ln φ_i)/∂T [1/K].
    private final double[]
    lnPhi
    Log fugacity coefficients ln(φ_i).
    private final int
    numberOfComponents
    Number of components.
    private final int
    phaseIndex
    Phase index (0 = liquid-like, 1 = vapor-like).
    private final String
    phaseType
    Phase type description.
    private static final long
    serialVersionUID
     

  • Constructor Summary

    Constructors
    Constructor
    Description
    FugacityJacobian(int phaseIndex, String phaseType, double[] lnPhi, double[] dlnPhidT, double[] dlnPhidP, double[][] dlnPhidn, String[] componentNames)
    Constructor for FugacityJacobian.

  • Method Summary

    Modifier and Type
    Method
    Description
    boolean
    checkSymmetry(double[] moles, double tolerance)
    Check thermodynamic consistency (symmetry of composition Jacobian).
    double
    directionalDerivative(int componentIndex, double deltaT, double deltaP, double[] deltaN)
    Compute directional derivative of ln(φ_i) along a perturbation.
    String[]
    getComponentNames()
    Get component names.
    double[][]
    getDlnPhidn()
    Get full composition Jacobian matrix.
    double
    getDlnPhidn(int i, int j)
    Get derivative of ln(φ_i) w.r.t. moles of component j.
    double[]
    getDlnPhidnRow(int componentIndex)
    Get row of composition Jacobian (derivatives of ln(φ_i) w.r.t. all component moles).
    double[]
    getDlnPhidP()
    Get all pressure derivatives.
    double
    getDlnPhidP(int componentIndex)
    Get derivative of ln(φ_i) w.r.t. pressure.
    double[]
    getDlnPhidT()
    Get all temperature derivatives.
    double
    getDlnPhidT(int componentIndex)
    Get derivative of ln(φ_i) w.r.t. temperature.
    double[]
    getLnPhi()
    Get all log fugacity coefficients.
    double
    getLnPhi(int componentIndex)
    Get log fugacity coefficient for a component.
    int
    getNumberOfComponents()
    Get number of components.
    int
    getPhaseIndex()
    Get phase index.
    String
    getPhaseType()
    Get phase type description.
    String
    toString()
     

    Methods inherited from class Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

  • Field Details

    • serialVersionUID

      private static final long serialVersionUID
      See Also:

    • phaseIndex

      private final int phaseIndex
      Phase index (0 = liquid-like, 1 = vapor-like).

    • phaseType

      private final String phaseType
      Phase type description.

    • numberOfComponents

      private final int numberOfComponents
      Number of components.

    • lnPhi

      private final double[] lnPhi
      Log fugacity coefficients ln(φ_i).

    • dlnPhidT

      private final double[] dlnPhidT
      Derivatives w.r.t. temperature: ∂(ln φ_i)/∂T [1/K].

    • dlnPhidP

      private final double[] dlnPhidP
      Derivatives w.r.t. pressure: ∂(ln φ_i)/∂P [1/bar].

    • dlnPhidn

      private final double[][] dlnPhidn
      Derivatives w.r.t. moles: ∂(ln φ_i)/∂n_j [1/mol]. Matrix is [component][d/dn_component].

    • componentNames

      private final String[] componentNames
      Component names.

  • Constructor Details

    • FugacityJacobian

      public FugacityJacobian(int phaseIndex, String phaseType, double[] lnPhi, double[] dlnPhidT, double[] dlnPhidP, double[][] dlnPhidn, String[] componentNames)
      Constructor for FugacityJacobian.
      Parameters:
      phaseIndex - phase index
      phaseType - phase type description
      lnPhi - log fugacity coefficients
      dlnPhidT - derivatives w.r.t. temperature
      dlnPhidP - derivatives w.r.t. pressure
      dlnPhidn - derivatives w.r.t. moles (Jacobian matrix)
      componentNames - component names

  • Method Details

    • getPhaseIndex

      public int getPhaseIndex()
      Get phase index.
      Returns:
      phase index

    • getPhaseType

      public String getPhaseType()
      Get phase type description.
      Returns:
      phase type

    • getNumberOfComponents

      public int getNumberOfComponents()
      Get number of components.
      Returns:
      number of components

    • getLnPhi

      public double getLnPhi(int componentIndex)
      Get log fugacity coefficient for a component.
      Parameters:
      componentIndex - component index
      Returns:
      ln(φ_i)

    • getLnPhi

      public double[] getLnPhi()
      Get all log fugacity coefficients.
      Returns:
      array of ln(φ_i)

    • getDlnPhidT

      public double getDlnPhidT(int componentIndex)
      Get derivative of ln(φ_i) w.r.t. temperature.
      Parameters:
      componentIndex - component index
      Returns:
      ∂(ln φ_i)/∂T [1/K]

    • getDlnPhidT

      public double[] getDlnPhidT()
      Get all temperature derivatives.
      Returns:
      array of ∂(ln φ_i)/∂T

    • getDlnPhidP

      public double getDlnPhidP(int componentIndex)
      Get derivative of ln(φ_i) w.r.t. pressure.
      Parameters:
      componentIndex - component index
      Returns:
      ∂(ln φ_i)/∂P [1/bar]

    • getDlnPhidP

      public double[] getDlnPhidP()
      Get all pressure derivatives.
      Returns:
      array of ∂(ln φ_i)/∂P

    • getDlnPhidn

      public double getDlnPhidn(int i, int j)
      Get derivative of ln(φ_i) w.r.t. moles of component j.
      Parameters:
      i - component index for fugacity
      j - component index for differentiation
      Returns:
      ∂(ln φ_i)/∂n_j [1/mol]

    • getDlnPhidnRow

      public double[] getDlnPhidnRow(int componentIndex)
      Get row of composition Jacobian (derivatives of ln(φ_i) w.r.t. all component moles).
      Parameters:
      componentIndex - component index
      Returns:
      array of ∂(ln φ_i)/∂n_j for all j

    • getDlnPhidn

      public double[][] getDlnPhidn()
      Get full composition Jacobian matrix.
      Returns:
      matrix [i][j] = ∂(ln φ_i)/∂n_j

    • getComponentNames

      public String[] getComponentNames()
      Get component names.
      Returns:
      array of component names

    • checkSymmetry

      public boolean checkSymmetry(double[] moles, double tolerance)
      Check thermodynamic consistency (symmetry of composition Jacobian).

      For a thermodynamically consistent model: n_i * ∂(ln φ_i)/∂n_j = n_j * ∂(ln φ_j)/∂n_i

      Parameters:
      moles - mole numbers
      tolerance - relative tolerance for symmetry check
      Returns:
      true if consistent within tolerance

    • directionalDerivative

      public double directionalDerivative(int componentIndex, double deltaT, double deltaP, double[] deltaN)
      Compute directional derivative of ln(φ_i) along a perturbation.
      Parameters:
      componentIndex - component index
      deltaT - temperature perturbation
      deltaP - pressure perturbation
      deltaN - mole perturbations
      Returns:
      directional derivative of ln(φ_i)

    • toString

      public String toString()
      Overrides:
      toString in class Object