24.5.6 Modeling Compressible Flows

You can model compressible multiphase flows, and can use it in conjunction with the energy multiphase equations and available multiphase turbulence models. When using the Eulerian multiphase model for a compressible flow, note the following:

• While you can specify both compressible gas phases and compressible liquid phases, you can only define one of the phases as a compressible ideal gas (i.e., you can select the ideal-gas for the density in the Create/Edit Materials dialog box of only one phase's material). There is no limitation on using compressible liquids using user-defined functions.

• You can define only one compressible fluid phase.

• For each mass flow inlet, you will need to specify mass flow or mass flux for each individual phase.

• If you specify the total pressure at a boundary (e.g., for a pressure inlet or intake fan), ANSYS FLUENT will use the specified value for temperature at that boundary as total temperature for the compressible phase, and as static temperature for the other phases (which are incompressible).

  Note that if you read a case file that was set up in a version of ANSYS FLUENT previous to 6.1, you will need to redefine the conditions at the mass flow inlets. See Section  24.2.9 for more information on defining conditions for a mass flow inlet in Eulerian multiphase calculations.

See Section  9.4 for more information about compressible flows.