8.7.4 Specific Heat Capacity as a Function of Composition

If you are modeling a flow that includes more than one chemical species (multicomponent flow), you have the option to define a composition-dependent specific heat capacity. (Note that you can also define the heat capacity of the mixture as a constant value or a function of temperature, or using kinetic theory.)

To define a composition-dependent specific heat capacity for a mixture, follow these steps:

1.   For the mixture material, choose mixing-law in the drop-down list to the right of Cp.

2.   Click Change/Create.

3.   Define the specific heat capacity for each of the fluid materials that comprise the mixture. You may define constant or (if applicable) temperature-dependent heat capacities for the individual species. You may also use kinetic theory for the individual heat capacities, if applicable.

The solver will compute the mixture's specific heat capacity as a mass fraction average of the pure species heat capacities: