Setting the Multi-Component Gas Properties and Initial Conditions

Define the gas components in the gas continuum and set their properties.

To set the multi-component gas properties and initial conditions:

  1. Right-click Multi-Component Gas > Gas Components and choose Select Mixture Components.
  2. In the Select Mixture Components dialog, expand the Material Databases > Standard > Gases node and select the following gases: H2O (Water), C2H4 (Ethylene), and Air (Air).


  3. Click Apply, and then Close.

Specify custom properties to model ethylene glycol vapor.

  1. Rename the Gas Components > C2H4 node to C2H6O2, the chemical symbol for ethylene glycol.
  2. Select the Gas Components > C2H6O2 > Material Properties > Molecular Weight > Constant node and change its Value to 62.07 kg/kmol.


Set the initial conditions for the multi-component gas continuum. The gas is initially at 293.15 K.

  1. Select Continua > Physics 1 > Initial Conditions > Static Temperature and set Value to 293.15 K.

The gas initially consists of 99% dry air and 1% water vapor.

  1. Select Continua > Physics 1 > Initial Conditions > Species Mass Fraction and click (Custom Editor) for the Value property.
  2. In the Species Mass Fraction - Value dialog, set the values of H2O and Air to 0.01 and 0.99 respectively.


    The sum of all mass fractions must be equal to 1.0.

  3. Click OK.