Topology Physics Model Reference

The Topology Physics model simulates the effects of solid material distributed within a fluid. In Simcenter STAR-CCM+ this model is generally used in conjunction with the Topology Optimization model and Adjoint model. However, it can be used in isolation with an external optimizer.

Table 1. Topology Optimization Model Reference
Provided By [physics continuum] > Models > Optional Models
Example Node Path Continua > Physics 1 > Models > Topology Physics
Requires
  • Time: Steady
  • Flow: Coupled Flow
Properties See Topology Physics Model Properties.
Incompatible Models
  • Flow: Segregated Flow
  • Flow: Viscous Flow
  • Material: Multiphase
  • Material: Multi-component
  • Equation of State: Polynomial Density
  • Equation of State: User defined EOS
  • Equation of State: Thermal Non-Equilibrium Ideal Gas
  • Optional Models: Porous Media
  • Optional Models: Lagrangian Multiphase
  • Optional Models: Radiation
  • Optional Models: Harmonic Balance
  • Optional Models: Passive Scalar
NoteThe topology physics treatment cannot be applied to a porous region. However, that doesn't stop you from having a porous region interfacing the topology optimization region, as long as the topology optimization region is a regular fluid region.
Compatible Meshers
  • Trimmed Cell Mesher
  • Polyhedral Mesher
  • Tetrahedral Mesher
  • Thin Mesh Mesher
  • Advanced Layer Mesher
Activates Field Functions See Topology Physics Field Functions.

Topology Physics Model Properties

Brinkman Penalization Magnitude
Provides the scaling factor α in the momentum equation Eqn. (5137). It models a solid blockage in the flow as porous media with a very small porosity.

The correct setting of the Brinkman Penalization Magnitude can be determined by monitoring the velocity magnitude in the solid phase (Material Indicator = 0). In case that the magnitude is not a small percentage of the fluid velocity magnitude, the penalization should be increased.

Solid Phase
  • Regions

    Specifies the region(s) in which the topology optimization is applied.

Solid Phase > Models
Manages the physics models for the additional solid phase of the topology physics model. Select the following two models if the energy equation is activated in the physics continuum:
  • Material: Solid
  • Equation of State: Constant Density

Topology Physics Field Functions

The following field functions are made available when applying Topology Physics Model.

Material Indicator
Defines the material distribution.
  • The value 1 indicates the primary (fluid) material defined in the physics continuum.
  • The value 0 indicates the solid material defined in the Topology Physics model.
Topology Interface Indicator
Indicates the fluid/solid interfaces within the domain. This quantity which ranges between 0 and 1 is the basis for modification of the linear system in the PDE wall distance solver. Cells identified as a material interface (i.e wall) are input as a wall boundary condition to the wall distance solver, consequently the wall distance is then set to zero for those cells. Only available with the PDE wall distance method for turbulence of the primal flow while solving topology physics.