In homogeneous multiphase flow, a common flow field is shared by all fluids, as well as other relevant fields such as temperature and turbulence. This allows some simplifications to be made to the multifluid model resulting in the homogeneous model.

For a given transport process, the homogeneous model assumes that the transported quantities (with the exception of volume fraction) for that process are the same for all phases, that is,

(5–18)

Because transported quantities are shared in homogeneous multiphase flow, it is sufficient to solve for the shared fields using bulk transport equations rather than solving individual phasic transport equations.

The bulk transport equations can be derived by summing the individual phasic transport equations (Equation 5–206) over all phases to give a single transport equation for :

(5–19)

where:

(5–20)

The homogeneous model does not need to be applied consistently to all equations. For example, the velocity field may be modeled as inhomogeneous, but coupled with a homogeneous turbulence model. Alternatively, a homogeneous velocity field may be coupled with inhomogeneous temperature fields. Homogeneous Additional Variables are also available in CFX.