The Euler-Euler Model, Turbulent Flow (ee) interface (
), found under the
Multiphase Flow>Euler-Euler Model branch (
) when adding a physics interface, can be used to simulate high Reynolds number flow of a two-phase mixture containing a continuous and a dispersed phase. The Euler-Euler model assumes that both phases are continuous, fully interpenetrating, and incompressible (see
Theory for the Euler-Euler Model Interfaces). Typical applications for the interface are fluidized beds (solid particles in gas), sedimentation (solid particles in liquid), or transport of liquid droplets or bubbles in a liquid.
Two-phase turbulence is modeled using the standard two-equation k-
ε model with realizability constraints. The interface includes the possibility to solve one set of
k-
ε equations for the two-phase mixture, or to solve two sets of
k-
ε equations, one for each phase. Flow close to walls is modeled using wall functions.
By default the Two-Phase Turbulence is defined as
Mixture. This implies that one set of
k-
ε equations are solved for. To instead solve for two sets of
k-
ε equations, one for each fluid phase, select
Phase specific (see
Turbulent Two-Phase Flow Modeling).
To display this section, click the Show More Options button (
) and select
Advanced Physics Options. The
Turbulence variables scale parameters subsection is available when the
Turbulence model type is set to
RANS, k-ε.
The Uscale and
Lfact parameters are used to calculate absolute tolerances for the turbulence variables. The scaling parameters must only contain numerical values, units or parameters defined under
Global Definitions. The scaling parameters cannot contain variables. The parameters are used when a new default solver for a transient study step is generated. If you change the parameters, the new values take effect the next time you generate a new default solver.