Selecting the Physics Models
Physics models define the primary variables of the simulation, including pressure, temperature, velocity, and what mathematical formulation is used to generate the solution.
Three continua are set up to model each of the three regions.
To set up the physics models for the coolant:
- For the physics continuum, , in the Enabled Models group box, deactivate Two-Dimensional.
-
Select the following models in order:
Group Box
Model
Space
Axisymmetric
Time
Steady
Material
Multiphase
Multiphase Interaction (Selected automatically)
Multiphase Model
Eulerian Multiphase (EMP)
Gradients (Selected automatically)
Viscous Regime
Turbulent
EMP Turbulence Phasic Turbulence (selected automatically) Optional Models
Gravity
Phase Coupled Fluid Energy
- Click Close.
- Rename the Physics 1 node to Coolant.
-
To review the models, open the
node.
- Save the simulation.
To assign the Coolant continuum to the Coolant region:
-
Select the
node and set its
Physics Continuum to
Coolant.
To set up the physics models for the cladding and fuel:
- For the physics continuum, , in the Enabled Models group box, deactivate Two-Dimensional.
-
Select the following models in order:
Group Box
Model
Space
Axisymmetric
Time
Steady
Material
Solid
Optional Models
Segregated Solid Energy
Gradients (Selected automatically)
Equation of State
Constant Density
- Click Close.
The physics models for the cladding and fuel are identical. However, since different material properties are used to model each region, two separate continua are created for the cladding and fuel:
- Right-click and select Copy.
- Right-click Continua and select Paste.
- Select the copy and rename it to Cladding.
- Rename Physics 2 to Fuel.
-
Assign these two continua to their respective regions.
The icons of the Fuel and Cladding regions turn to gray to indicate that they are both solid regions.
- Save the simulation.