TDE Equation of State (EOS) Menu

Read Only EOS

These EOS Menu items allow access to a stored EOS for a particular compound for (1) comparison with the experimental data available with TDE and (2) property evaluation with the EOS. The equations are "Read Only" in that no alteration of the equation parameters is possible.

• RefProp EOS (read only): Open an evaluated EOS available in NIST Standard Reference Database 23 (REFPROP). These evaluated EOS are available for <100 compounds.


• Open EOS (read only) : Open an EOS evaluated previously with TDE. This feature is available for evaluated Span-Wagner type equations only.

EOS for Fitting

These EOS Menu items start the EOS Fitting Process of the selected EOS to the experimental and predicted property data. Descriptions of the equations and general descriptions of their application are provided through the links below.

The following EOS (in combination with heat capacities for the ideal-gas state) may be used for comprehensive calculation of thermodynamic properties.

• Span-Wagner (Non-Polar)


• Span-Wagner (Polar)


• Open EOS Equation (for fitting): Open a Span-Wagner type EOS evaluated previously with TDE as a starting point for a new evaluation.

The following EOS are commonly used for less comprehensive representation of thermodynamic properties.

• PC-SAFT


• Modified Sanchez-Lacombe


• Translated Peng-Robinson

The Model Fitting Control Center

The Model Fitting Control Center is the TDE interface for control of the EOS Fitting Process.

• Model Fitting Control Center: Open the Model Fitting Control Center.

• Purpose of TDE
• Critically Evaluated Properties
• Pure Component Properties
• Binary Mixture Properties
• Ternary Mixture Properties
• Reaction Properties
• Material Stream Properties
• How to do EVALUATIONS
• Evaluation for PURES
• Compound Selection (Pures)
• Add User Data (Pures)
• "Superstructure" Component Search
• Evaluation for BINARIES
• Component Selection (Binary)
• Component 1 Selection
• Component 2 Selection
• Add User Data (Binary)
• Evaluation for TERNARIES
• Component Selection (Ternary)
• Add User Data (Ternary)
• Evaluation for REACTION
• Reaction Selection
• Participant Selection
• Formation Properties Evaluation
• Evaluation for MATERIAL STREAM
• Component Selection (Stream)
• Apply/Fit AC Model to Sub-Systems
• Add Composition
• Add Property Calculation
• Explore Calculation Results
• Save Results
• The Main Screen Menus
• File Menu
• View Menu
• Action Menu
• Equation of State (EOS) Menu
• Mixture Menu
• Product Design Menu
• Experiment Planning Menu
• Updates Menu
• The Main Screen Window
• Navigation Tree (Pures)
• Compound
• Property Name/Phase Formats
• Expt and Predicted Data
• Reaction Data
• Default Equations
• Property Consistency
• Evaluated Data
• Evaluated Enthalpy of Formation
• Alternative Equations
• Equations of State
• Calculated with EOS
• Navigation Tree (Mixtures)
• Components of Binary Mixture
• Expt and Predicted Data
• VLE Data Summary View (Binary)
• VLE Datasets & Consistency Tests
• VLE Datasets
• VLE Consistency Tests
• VLE Data Summary View (Ternary)
• LLE Data Summary View (Binary)
• LLE Data Summary View (Ternary)
• Expt Data (Display only)
• Single Property Equations
• Calc w/ Single-Property Eq's
• Multi-Property Equations (Binaries)
• Multi-Property Equations (Ternaries)
• VLE Model/Data Comps (Ternary)
• LLE Model/Data Comps (Ternary)
• Calc w/ Multi-Property Eq's
• Navigation Tree (Reactions)
• Properties of Participants
• Expt and Predicted Data
• Consistency with Participant Data
• Evaluated Reaction Data
• Navigation Tree (Material Stream)
• Components
• Binary Sub-Systems (A + B)
• Composition Number
• Add Composition
• Calculation Number
• Add Calculation
• Property Nomenclature (Mixtures)
• Property Nomenclature: SLE
• Property Nomenclature: LLE
• Property Nomenclature: VLE
• Data Table Features
• Data Tables (General Info)
• Bibliographic Info (Data Source)
• Sort Data
• Select Data Set (or Single Value)
• Plot Data
• VLE Data Summary (Binaries)
• VLE Data Summary (Ternaries)
• LLE Data Summary (Binaries)
• LLE Data Summary (Ternaries)
• Flawed Data
• Plot Features
• Plot Legend (Colors)
• Plots: General Info (Pures)
• Right-Click Features (Pures)
• Plots: General Info (Binary)
• Right Click Features: (Binary)
• Single-Property Equations (Pures)
• Vapor Pressure
• Sublimation Pressure
• Crystal-Liquid boundary
• Density (sat liquid)
• Density (sat vapor)
• Density (liquid- 1 phase)
• Density (gas- 1 phase)
• Enthalpy of Vaporization
• Enthalpy of Sublimation
• Heat Capacity (Csat- crystal)
• Heat Capacity (Csat- liquid)
• Heat Capacity (Ideal Gas)
• Entropy & Enthalpy, derived (crystal)
• Entropy & Enthalpy, derived (liquid)
• Speed of Sound (liquid)
• Speed of Sound (gas)
• Refractive Index (liquid)
• Surface Tension
• Viscosity (sat liquid)
• Viscosity (gas)
• Thermal Conductivity (sat liquid)
• Thermal Conductivity (gas)
• Single-Property Equations (Binaries)
• Single-Property Equations (Ternaries)
• EOS Fitting (Pures)
• EOS Fitting Process (Pures)
• EOS: Equations Supported (Pures)
• Span-Wagner
• PC-SAFT
• Modified Sanchez-Lacombe
• Peng-Robinson (Original)
• Peng-Robinson (Twu)
• Peng-Robinson (Mathias-Copeman)
• Peng-Robinson (SRW)
• REFPROP (Read Only)
• TDE Generated (Read Only)
• Activity Coeff. Model Fitting (Mixtures)
• AC Model Fitting (Binaries)
• Model Fitting Control Center
• Model Configuration Form
• Activity Coeff. Models (Binaries)
• UNIFAC Prediction (Original)
• UNIFAC Prediction (NIST-KT)
• UNIFAC Prediction (NIST-Modified)
• NIST-COSMO-SAC Prediction
• NRTL
• Redlich-Kister
• UNIQUAC
• Van Laar
• Wilson
• Activity Coeff. Model Calcs. (Ternaries)
• Gas-Phase Models (Mixtures)
• Special Displays: VLE-LLE-SLE
• VLE Consistency Tests (Binary)
• VLE Isotherm Plot (Binary)
• VLE Isobar Plot (Binary)
• VLE Plot for Peng-Robinson EOS
• VLE Isopleth Plot for P-R EOS
• Azeotropic Data (Binary)
• LLE Diagram (Binary)
• SLE Diagram (Binary)
• LLE Diagram (Ternary)
• VLE Gas Composition (Ternary)
• Uncertainties
• Uncertainties in Tables & Plots
• Uncertainty Definitions
• Output Files & Formats
• Eq Parameter Definitions
• Eq Parameter O/P
• TDE-SOURCE Data Archive
• Web Updates
• Database Version Control
• Show TDE-SOURCE Version
• Addition of User Data
• Structure Drawing
• Prediction Methods (Pures)
• Formation Reaction Properties
• Properties of Elements
• NIST/REFPROP Database in TDE
• Product Design
• Pure Compound
• Solvent for Solid
• Specify Solute
• Enter Temperature
• Add Solvent Efficiency
• Add Solvent Property
• Specify Compound Class
• Select Database
• Select Model Basis
• Search and Results
• Explore Results
• Save Results
• Selective Solvent for Solid Mixture
• Specify Solute & Contaminant
• Enter Temperature
• Add Solvent Efficiency
• Add Solvent Property
• Specify Compound Class
• Select Database
• Select Model Basis
• Search and Results
• Explore Results
• Save Results
• Solvent for Extraction
• Specify Solute & Carrier
• Enter Temperature
• Add Solvent Efficiency
• Add Solvent Property
• Specify Compound Class
• Select Database
• Select Model Basis
• Search and Results
• Explore Results
• Save Results
• Experiment Planning
• Evaluate Measurement (Pure)
• Evaluate Measurement (Binary)
• Recommend Measurements (Pure)
• UNIFAC Extension
• ThermoML- IUPAC Standard
• References
• Glossary
• FAQ

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