Activating FMU Co-Simulation Models

Prepare the Simcenter STAR-CCM+ simulation and add the physics models that enable co-simulation with FMU.

  1. Launch the Simcenter STAR-CCM+ simulation that you want to couple with an FMU model. If the FMU requires external libraries, specify the path to these libraries using the -ldlibpath option. For more information, see Server Options.
    For example, for co-simulation with Simcenter Amesim through an imported FMI library, include the path to the Simcenter Amesim co-simulation libraries.
  2. Before you define co-simulation settings, make sure that the uncoupled Simcenter STAR-CCM+ simulation runs to convergence.
    To test the simulation, you can use provisional boundary conditions that are close to the values expected from the FMU.
When you are satisfied with the solution, modify the simulation to enable co-simulation:
  1. Expand the Continua node.
For co-simulation with FMU, you require two physics continua—one continuum for the physics that are solved in Simcenter STAR-CCM+ (the internal continuum) and one continuum that represents the physics in the FMU (the external continuum).
  1. Create a physics continuum for the Simcenter STAR-CCM+ physics and select the physics models that are required in your analysis.
  2. For the internal physics continuum, add the following physics models:
    Group Physics Model
    Optional Models Co-Simulation
    Co-Simulation Models FMI

    For information on the FMI model requirements, see FMI Co-Simulation Models Reference.

  3. Assign the internal continuum to the relevant Simcenter STAR-CCM+ region.
  4. To represent the external physics, create a new physics continuum. For this continuum, select the following models:
    Group box Model
    Optional Models External Continuum
    External Continuum External Application (selected automatically)
    Space Network
    External Application FMI (selected automatically)
    Optional Models Implicit Unsteady, Explicit Unsteady, or PISO Unsteady
    Example continua are shown in the following image:

Create a region to represent the FMU and assign the external continuum to this region:
  1. Right-click the Regions node and select New.
  2. Select the Regions > [FMU Region] node and set Physics Continuum to the external continuum.
The External Continuum model indicates that the physics is defined by an external application. When you activate this model, Simcenter STAR-CCM+ adds a link node to the simulation tree, External Links > [Link 1]. A link represents the connection to an external application and allows you to set the relevant co-simulation settings.

For the link, you specify the external continuum that represents the external application:

  1. Select the [Link 1] > Conditions > External Continua node and set Continua to the external physics continuum that represents the FMU.
    Simcenter STAR-CCM+ automatically sets the launch and connect options (under the [Link 1] > Conditions node) to the methods that are appropriate for FMU Co-Simulation.