Ok, doing numerical calculations in your browser seems somewhat weird, but as a proof-of-concept...

Yes, this means that the equilibrium code is running on the client side (i.e. your browser), using the JavaScript language.

The calculation of the equilibrium concentration is done minimizing numerically the Gibbs' free energy of the mixture. In principle the procedure is the same as the one proposed by W. C. Reynolds and realized in his famous STANJAN code.

[Reynolds, W. C. "The element potential method for chemical equilibrium analysis: Implementation in the interactive program STANJAN, version 3."Technical Rept." (1986)].

The thermodynamic data (and transport data, which are not used for calculation, but only displayed) for calculating the equilibrium concentrations are taken from various resources of the literature.

Select a species set, fill in the composition of your gas and select the calculation mode. Then press the calculate button.

The oxidator is always a mixture of O2 and N2 (i.e. air) but can vary by its mole fraction of O2

Calculation modes comprise several conditions: T:P - constant temperature and pressure, T:V - constant temperature and volume, P:V - constant pressure and volume, P:H - constant pressure and enthalpy, V:U - constant volume and internal energy, V:H - constant volume and enthalpy.

To enable a better overview, all species with a fraction of less than 1E-9 by mass are not displayed.

The query syntax of the URL can be used to give parameters already from the internet address. An example is:
another example is:


                  VBT Equilibrium Calculator


Air excess ratioλ-
O2 in airXO2,air-

    Fuel Air Mixture react.Mix.
T K        
ρ kg/m3        
λ W/m/K        
μ Pa s        
cp J/kg/K