FE-ISO20765-2, Ver. 1.00 is a program for MS Windows. FE-ISO20765-2 calculates the properties of a natural gas in accordance with International standards ISO 20765-2:2015 and ISO 14912:2003

FE-ISO20765-2 user interface

FE-ISO20765-2 screenshot

FE-ISO20765-2 ReadMe
Ver. 1.00, Feb 16, 2018.

FE-ISO20765-2 is a program for MS Windows.
FE-ISO20765-2 calculates the properties of a natural gas mixture in accordance with:
  • ISO-20765-2:2015: Natural gas - Calculation of thermodynamic properties -
    Part 2: Single-phase properties (gas, liquid, and dense fluid) for extended ranges of application
  • 2. ISO-14912:2003: Gas analysis - Conversion of gas mixture composition data
Download "fe_20765x2.exe", the latest version of self-extracting and self-installing demo program. Run "fe_20765x2.exe" and follow the on-screen instructions. The default folder for installation is C:\Program Files (x86)\FE_ISO20765_2.

Note: The text box for Methane is locked in unregistered version and can not be changed but you can still verify all the possibilities and options of registered FE-ISO20765-2 software.
RUN FE-ISO20765-2
After completing the installation run the program using the 'Start' menu of your task bar or double click the fe_iso20765_2.exe from your Windows Explorer.
To start the calculation select 'Calculate' from 'Run' menu of your FE-ISO20765-2 menu bar.
To save the file select 'Save As' from FE-ISO20765-2 'File' menu. The default file extension is '.i22'
To open the existing file select 'Open' from FE-ISO20765-2 'File' menu.
To print the results of the calculation to your system printer
select 'Print' from FE-ISO20765-2 'File' menu.
To print the calculation results into ASCII file select 'Print ASCII to File' from FE-ISO20765-2 'File' menu.
The following are the ranges of application (RAP) for input parameters:

Parameter Ranges
Range of application (RAP) R1 R2 R3
Absolute Pressure in MPa >0 to 35 >0 to 70 >0 to 70
Temperature in K 90 to 450 60 to 700 60 to 700
Mole fractions:
Methane 0.7 to 1 0.3 to 1 0 to 1
Nitrogen 0 to 0.2 0 to 0.55 0 to 1
Carbon dioxide 0 to 0.2 0 to 0.3 0 to 1
Ethane 0 to 0.1 0 to 0.25 0 to 1
Propane 0 to 0.035 0 to 0.14 0 to 1
n-Butane+Isobutane 0 to 0.015 0 to 0.06 0 to 1
n-Pentane+Isopentane 0 to 0.005 0 to 0.005 0 to 1
n-Hexane 0 to 0.001 0 to 0.002 0 to 1
n-Heptane 0 to 0.0005 0 to 0.001 0 to 1
n-Octane+n-Nonane+n-Decane 0 to 0.0005 0 to 0.0005 0 to 1
Hydrogen 0 to 0.1 0 to 0.40 0 to 1
Oxigen 0 to 0.0002 0 to 0.02 0 to 1
Carbon Monoxide 0 to 0.03 0 to 0.13 0 to 1
Water 0 to 0.00015 0 to 0.0002 0 to 1
Hydrogen Sulfide 0 to 0.0002 0 to 0.27 0 to 1
Helium 0 to 0.005 0 to 0.005 0 to 1
Argon 0 to 0.0002 0 to 0.0005 0 to 1

The ranges of applications defined by R1 and R2 are completely in accordance with ISO-20765-2:2015.
Mole fraction ranges defined by R3 are not in accordance with ISO-20765-2:2015. It can be used only for software testing purposes, like the examples given in Annex G of ISO-20765-2:2015, which do not satisfy the mole fraction ranges defined by R1 or R2.

In FE-ISO20765-2 a gas mixture analysis may be given in form of:
- Mole fractions
- Mass fractions
- Volume fractions at 100 kPa, 288.15 K
Note that mass or volume fractions may differ significantly from mole
fractions for the same gas mixture.
A sum of fractions of gas components must be between 0.99999 and 1.00001. If mass- or volume-fractions are given they will be internally converted to mole fractions during program execution, according to ISO-14912:2003, which then must satisfy the above mole fractions ranges.
We recommend the use of mole-, rather than mass- or volume-fractions, as the ISO-20765-2:2015 calculation procedures are based on mole-fractions exclusively.
The following calculation methods are implemented in FE_ISO20765_2:
A) Calculation based on: P, T and gas components fractions
B) Calculation based on: density, T and gas components fractions
C) Calculation based on: reduced density, T and gas components fractions

Regardless of the selected calculation method A), B) or C), the following input variables to FE-ISO20765-2 are common to all calculation methods:
  • Temperature [K]
  • Fractions of natural gas components
The results, common to all calculation methods, are:
  • Error status
  • Molar mass [kg/kmol]
  • Molar density [kmol/m3]
  • Compression []
  • Molar Gibbs free energy [kJ/kmol]
  • Molar internal energy [kJ/kmol]
  • Specific internal energy [kJ/kg]
  • Molar enthalpy [kJ/kmol]
  • Specific enthalpy [kJ/kg]
  • Molar entropy [kJ/(kmol⋅K)]
  • Specific entropy [kJ/(kg⋅K)]
  • Molar isochoric heat capacity [kJ/(kmol⋅K)]
  • Specific isochoric heat capacity [kJ/(kg⋅K)]
  • Molar isobaric heat capacity [kJ/(kmol⋅K)]
  • Specific isobaric heat capacity [kJ/(kg⋅K)]
  • Joule-Thomson coefficient [K/MPa]
  • Isentropic exponent []
  • Speed of sound [m/s]
Depending on the calculation method the following parameters could be input variables or results
  • Absolute pressure [MPa]
  • Density [kg/m3]
  • Reduced density []
In case of calculation method A), absolute pressure is the input variable while the density and reduced density are the results. In case of calculation method B), the density is the input variable while absolute pressure and reduced density are the results. In case of calculation method C), the reduced density is the input variable while absolute pressure and density are the results.

Before starting the calculation choose the corresponding calculation method, the ranges of application, the type of gas mixture analysis, and enter the input variables.
To convert your FE-ISO20765-2 demo program into fully functional version you need to buy the corresponding license.
After buying the license you will receive email with registration data, which will enable you to unlock your demo and convert it into the fully functional registered version.
To register the program, Run FE-ISO20765-2 as administrator! Select'Register' from 'Help' menu of your FE-ISO20765-2 menu bar and enter data exactly as described in the corresponding e-mail message.
This program is furnished under the license agreement and is protected by copyright law and international treaties.

You can download and try FELIB demonstration programs. Each demo-software is prepared as self-extracting and self-installing program for MS Windows environments.