Calculation of physical properties and phase equilibria

Program features

PROPER calculates physical properties and phase equilibria for pure substances and substance mixtures with up to 15 components according to relevant methods from [1,2]. It is based on a database with over 890 entries.

List of existing substances

The program is equipped with new, improved methods for physical properties calculation and context-sensitive help.

The PROPER program calculates:

up to 17 properties at one temperature or over a temperature range

  • Density
  • Thermal conductivity
  • Binary diffusion coefficients
  • Dynamic viscosity
  • Coefficient of thermal expansion
  • Prandtl number
  • Kinematic viscosity
  • Surface tension
  • Lewis number
  • Specific heat capacity cp
  • Enthalpy
  • Thermal diffusivity
  • Specific heat capacity cv
  • Evaporation enthalpy (pure substances)
  • Molecular weight (mixtures of substances)
  • Isentropic exponent cp/cv
  • Compressibility factor

Phase eqilibria of pure substances or of mixtures of substances.

The scope of the program has been broadened with a method for the calculation of specific heat capacity of monovalent alcohols, such as methanol, ethanol and propanol. The refrigerants R22, R23, R32, R123, R134a, R142b, R152a and R410a have also been added to the database.

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The results can be exported to MS Excel or as a text file.

There is a conversion of units for temperature and pressure.
    Temperature in °C, K, °F
    Pressure in N/m², pa, hPa, kPa, MPa, bar, mbar, psi
    The selected units are transferred to the documentation.

The calculation of the viscosity of gas mixtures has been improved.

Calculation equations from the VDI Heat Atlas 11th edition have been implemented.

The search for components has been simplified. You can search for the CAS number, the chemical formula, the German designation and the English designation.

In addition, PROPER can be called from all modules of the ATLAS program system for the calculation of physical properties. An automatic transfer of the determined physical properties is integrated.

Program PROPER (1 licence):  2100 EUR plus VAT


1. CUT properties

For special applications, properties of hydrocarbon cuts are available. The calculation starts with the ASTM D-86 curve or with the Watson factor UopK.

Extra charge: 600 EUR plus VAT

2. Phase equilibria

Calculation of the gas-liquid phase equilibrium according to the PSRK method for a maximum of 10 components. The calculation is based on the Dortmund database of DDBST GmbH / Oldenburg (Prof. Gmehling). The method is recommended for strongly real systems. The properties of the gas and liquid phase are calculated with the determined gas and liquid concentrations. The program is not suitable for systems with a mixing gap, i.e. systems where the liquid phase breaks down into two separate phases (e.g. water-oil mixtures).

Extra charge: 500 EUR plus VAT

3. PROP module as interface module to MS-EXCEL

Extra charge: 450 EUR plus VAT


[1] Reid R. C., Prausnitz J. M., Poling B. E. “The Properties of Gases & Liquids”, McGraw Hill, 4th edition 1987

[2] Poling Bruce E., Prausnitz John M., O’Connell John P. “The Properties of Gases & Liquids”, McGraw Hill, 5th edition 2001

see also:

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