Simcenter STAR-CCM+ Co-Simulation Models Reference

Internal Physics Continuum

The internal physics continuum represents the physics that is solved in the current simulation. This continuum contains the Simcenter STAR-CCM+ co-simulation model, which enables co-simulation with another Simcenter STAR-CCM+ simulation. Additionally, this continuum can contain co-simulation treatment models, which enable automatic set up of boundary conditions based on imported mechanical fields. See Exchanged Fields Reference.

Table 1. Co-Simulation Models
Model Names	Simcenter STAR-CCM+		Enables co-simulation with another Simcenter STAR-CCM+ simulation.
Provided By	[physics continuum] > Models > Co-Simulation Models
Example Node Path	Continua > Physics 1 > Models > Simcenter STAR-CCM+
Requires	Physics Models: Space: Three Dimensional Time: Steady or Implicit Unsteady Material: any Optional Models: Co-Simulation
Activates	Boundary Inputs	`External Code Coupling Specification`. See Boundary Settings.
	Region Inputs	`External Code Coupling Specification`. See Region Settings.
	Solvers	Simcenter STAR-CCM+ Co-Simulation
	Field Functions	Co-Simulation Exchange. See Field Functions.
	Other Nodes	External Links

Table 2. Co-Simulation Treatment Models
Model Names	Co-Simulation Mechanical Treatment	Enable automatic set up of boundary conditions based on the imported mechanical and thermal predefined fields. See Exchanged Fields Reference.
	Co-Simulation Thermal Treatment
Provided By	[physics continuum] > Models > Co-Simulation Treatment Models
Example Node Path	Continua > Physics 1 > Models > Co-Simulation Mechanical Treatment
Requires	Physics Models: Space: Three Dimensional Time: Steady or Implicit Unsteady Material: any Optional Models: Co-Simulation Co-Simulation Models: Simcenter STAR-CCM+

External Physics Continuum

The external physics continuum represents the partner simulation. This continuum contains a coupling model, which determines the coupling scheme that the current simulation uses to exchange data with the partner.

Table 3. Coupling Models
Model Names	Steady Coupling		Available for steady simulations.
	Explicit Coupling		Available for transient simulations. Allows the simulations to exchange data once per time-step.
	Implicit Coupling		Available for transient simulations. Allows the simulations to exchange data more than once per time-step.
Provided By	[physics continuum] > Models > Coupling Models
Example Node Path	Continua > Physics 1 > Models > Implicit Coupling
Requires	Physics Models: Optional Models: External Continuum External Continuum: External Application Space: Surface Three Dimensional External Application: Simcenter STAR-CCM+ Time: Steady or Implicit Unsteady
Activates	Solvers	Simcenter STAR-CCM+ Co-Simulation Multiphysics Stabilization Solver (Activated from the Simcenter STAR-CCM+ Co-Simulation solver node, only available in solid simulations with Implicit Coupling). See Multiphysics Stabilization Solver Reference.
	Other Nodes	External Links > Link 1 . See STAR-CCM+ Link Reference.
	Stopping Criteria	Activated by Implicit Coupling: Inner Last Step Stopping Criterion Outer Last Step Stopping Criterion

Boundary Settings

Available for boundaries of type: Outlet, Mass Flow Inlet, Pressure Outlet, Velocity Inlet, Stagnation Inlet, and Wall.

External Code Coupling Specification: Allows you to assign the boundary to a co-simulation zone for coupling. During the co-simulation, the Simcenter STAR-CCM+ boundary exchanges data with the corresponding coupled surface in the partner simulation, according to the co-simulation zone specifications.

Region Settings

Available for all type of regions. Only available for volume-to-volume coupling.

External Code Coupling Specification

Allows you to assign the region to a co-simulation zone of type Volume Zone for coupling. During the co-simulation, the Simcenter STAR-CCM+ region exchanges data with the corresponding coupled volume in the partner simulation, according to the co-simulation zone specifications.

Note	Volume-to-volume coupling requires you to specify any imported or exported fields using auxiliary fields.

Solvers

Simcenter STAR-CCM+ Co-Simulation

The Simcenter STAR-CCM+ Co Simulation solver has the following properties:

Multiphysics Stabilization Solver—only available when you activate the Implicit Coupling model. Allows you to specify the Stabilization Method to improve convergence. See Multiphysics Stabilization Solver Reference.
Solver Frozen—when activated, prevents the solver from updating the solution while iterating or responding to other solvers.
Temporary Storage Retained—when activated, Simcenter STAR-CCM+ retains additional field data the solver generates during an iteration. The particular data retained depends on the solver, and becomes available as field functions during subsequent iterations. Deactivated by default.

Multiphysics Stabilization Solver

See Multiphysics Stabilization Solver Reference

Stopping Criteria

Inner Last Step Stopping Criterion: Allows you to terminate the current time-step before the maximum number of data exchanges is reached if the current time-step of the partner simulation is finished.
Outer Last Step Stopping Criterion: Terminates the simulation if the partner simulation is finished. Activated automatically by Simcenter STAR-CCM+ Co-Simulation solver on both the fluid and solid side when the Implicit Coupling model is activated.

Field Functions

Co-Simulation Exchange: Represents the number of exchanges between the coupled simulations.