I am using ANSYS FLUENT to model a two-phase flow of liquid and gas using the Eulerian model where the surface tension force is included.

In the theory of the VOF model, the surface tension force is added to the momentum equation as a source term. However, in the Eulerian model, we have two momentum equations, one for the liquid and one for the gas.

How is the surface tension force included? is it added to the liquid momentum equation?is it added to the gas momentum equation? is it split between the two phases? If it is split, is it split by two volume averaged factors or two mass averaged factors?

Unfortunately, the theory manual does not mention related information under the Eulerian model theory.