Abaqus Link Reference

In Simcenter STAR-CCM+, you specify the settings for co-simulation with Abaqus in a link node under the External Links node.

A co-simulation link, External Links > [Link 1], appears in the simulation tree when you activate the Abaqus co-simulation model. This node allows you to specify co-simulation global settings, such as the connection method and concurrency mode, as well as to define and set up co-simulation zones, which define sets of boundaries, where fields are exchanged with the partner simulation.

For details on the co-simulation zone settings, see Co-Simulation Zones Reference.

[Link 1] Properties

Link Type: Describes the type of connection. Read-only.
Link Priority: Specifies the order in which the links are executed.

Link Models

In a Simcenter STAR-CCM+ simulation, you access the co-simulation framework by activating co-simulation models in the physics continua. These models determine the physics of the coupling, including the fields that can be exchanged with the partner simulation.

Link models configure the connection to a partner application or file. The link icon changes based on the application, or file, that Simcenter STAR-CCM+ connects to through the link. The link model must be appropriate for the co-simulation or file export model selected in the physics continuum.

[Link 1] Conditions and Values

You specify the general settings of the co-simulation under the [Link 1] > Conditions and [Link 1] > Values nodes. Some values are always available. Some values are triggered by conditions.

Abaqus Release

Allows you to specify which version of the partner software you are running. The available options include the recommended versions (see the section External Packages Support of the Simcenter STAR-CCM+ Release Notes), as well as a Custom option. The Custom option allows you to specify a version other than the recommended. In general, you are advised to use one of the recommended versions, as compatibility for other versions is not guaranteed. When using the Custom option, set the version using the Values > Custom Code Version node.

Load Partner Library Option

Allows you to specify the location of the Abaqus co-simulation library file.

On Linux, the required library file is libABQSMACseModules.so; on Windows, ABQSMACseModules.dll. The location of the library file depends on your Abaqus installation.

Option	Corresponding Condition/Value Nodes
Use Environment Variable Simcenter STAR-CCM+ loads the library from the location specified in the $SIMULIA_CSE_LIBPATH environment variable. This option requires you to define this environment variable on your system.	SIMULIA_CSE_LIBPATH Environment Variable Read-only. Displays the path to the library file that is saved in the environment variable $SIMULIA_CSE_LIBPATH.
Specify Library File Allows you to manually specify the path to the Abaqus library file.	Abaqus Library Specifies the absolute path to the Abaqus library file. You can type the full path manually, or you can click (Custom Editor) and navigate to the file using the file selection dialog.
Detect Partner Library Available only when you set `Abaqus Release` using the Custom option. Simcenter STAR-CCM+ automatically looks for the library file in the directory containing the Abaqus executable.	None

Launch Partner Option

Specifies how the Abaqus partner application is launched. The available options are:

Option	Corresponding Value Nodes
Launch Application When you run the co-simulation, Simcenter STAR-CCM+ automatically launches Abaqus based on the specified execution settings.	Abaqus Execution See Abaqus Execution. Assigned Partner Host:Port Displays the Host:Port connection for the partner application. (Read-only).
Do Not Launch Enables you to launch Abaqus via the command line.	Partner Host:Port Specify the Host:Port connection to the partner application.

Connect Option

Allows you to specify which method the simulation uses to connect to the partner simulation. The available options depend on the selected Launch Partner Option.

Option	Corresponding Value Node
Determined Automatically Simcenter STAR-CCM+ automatically connects to Abaqus based on the specified execution settings This option is available when the current simulation launches automatically, that is, when Launch Partner Option is set to Launch Application.	Assigned Partner Host:Port Displays the host and port where the partner simulation is running.
Host:Port Allows you to specify the host and port where the simulation is running. This option is available when you launch the simulation separately, that is, when Launch Partner Option is set to Do Not Launch.	Partner Host:Port Specifies the host and port where the partner simulation is running.

Mapping Option

Specifies whether Simcenter STAR-CCM+ or Abaqus maps the exchanged data. When coupling Simcenter STAR-CCM+ boundaries with Abaqus surfaces (surface-to-surface coupling), you can select either Simcenter STAR-CCM+ or Abaqus as the mapper code. However, coupling between Simcenter STAR-CCM+ boundaries and a node on the Abaqus model (surface-to-point coupling) is only available when you select Simcenter STAR-CCM+ as the mapper code. The available options are:

Map Both Directions: Simcenter STAR-CCM+ maps the imported solution data before the solver run starts and the exported solution data after the solver stops. Simcenter STAR-CCM+ maps its solution onto the Abaqus mesh before exchanging data with Abaqus. Abaqus exchanges its solution data with Simcenter STAR-CCM+, which then maps the Abaqus solution onto the Simcenter STAR-CCM+ mesh.

Partner Maps Both Directions: Abaqus maps the imported solution data before the solver run starts and the exported solution data after the solver completes.

Verbosity Level

Allows you to choose the solver verbosity, that is, the amount of information that is printed to the Output window.

Abaqus Solver

Specifies the type of solver in the Abaqus input file. You can set the option to Abaqus/Standard or Abaqus/Explicit. When Abaqus is launched Simcenter STAR-CCM+ changes this option if the solver detected in the Abaqus input file is different to that specified.

Coupling Negotiation Method

Specifies the method to determine the time interval between data exchanges. For all but the User Defined option, the time interval between exchanges is the same in both simulations. The available methods are:

Option	Corresponding Value Node
Constant The simulations exchange data at a specified time interval.	Transfer Interval Specifies the time interval between two consecutive data exchange events.
Min The simulations exchange data at a time interval equal to the smallest of the time-steps (either the current simulation time-step or the partner simulation time-step).	None
Max The simulations exchange data at a time interval equal to the largest of the time-steps (either the current simulation time-step or the partner simulation time-step).	None
Import The simulations exchange data at a time interval equal to the partner simulation time-step.	None
Export The simulations exchange data at a time interval equal to the current simulation time-step.	None
User Defined The simulations exchange data at specified independent time intervals. This option is useful if the simulations are running at different time scales.	`User-Defined Negotiation Method Controls` The available properties are: STAR-CCM+ Coupling Time Interval: Specifies the transfer interval for the Simcenter STAR-CCM+ simulation. Abaqus Coupling Time Interval: Specifies the transfer interval for the Abaqus analysis. Exported Field Calculation: Specifies the method that is used to calculate the field values that are exported to Abaqus. Choose Average, to average the field values over all time-steps between exchanges. Choose Instantaneous to export the field values as they appear at the time of exchange.

Displacement Reference Configuration Option: Specifies the coordinate configuration used by Abaqus to export displacements to Simcenter STAR-CCM+. If you mesh both the fluid and the structure using the same geometry, their original mesh configurations match, and you can set the reference configuration to the Original Mesh Coordinates for the first and subsequent (restart) co-simulations. If you mesh either the fluid or the structure using different configurations, use the Current Mesh Coordinates for the initial co-simulation. An example of this latter scenario is when the structure undergoes some deformation for pre-loading, and the fluid mesh is generated based on the deformed structure. You cannot modify the configuration option during the co-simulation run. To specify a different configuration, terminate the co-simulation, select the relevant configuration, the rerun the co-simulation.; The position and extent of the coupled fluid boundary and structure surface must match at the beginning of the co-simulation. Possible causes of a mismatch in position are: discretization differences, an error identifying the units that Abaqus uses, or the use of an incorrect reference configuration in the initial search. Each code reports initial (target) search failures for its coupled boundary/surface separately (in the Output window in Simcenter STAR-CCM+ and the .msg/.sta files in Abaqus).

External Code Restart

Allows you to specify resume files for co-simulation restart. For more information, see Restarting from a Previous Abaqus Simulation.

Restart Option	Corresponding Child Node
None The simulation is not set up for co-simulation restart.	None
New Step Defines a co-simulation restart step.	Abaqus Old Job Name Specifies the name of the old Abaqus job used for restart. The Abaqus restart files from the analysis defined by Old Job Name are read at the start of the co-simulation and must be present in the same directory as the Input File of the restart analysis.

Time-Marching Sequence: Defines whether Simcenter STAR-CCM+ and Abaqus run simultaneously or sequentially. For implicit coupling, only sequential runs are possible. For this node, you can set Option to:; Abaqus Leads: sets Abaqus and Simcenter STAR-CCM+ to run sequentially with Abaqus leading the co-simulation.; STAR-CCM+ Leads: sets Abaqus and Simcenter STAR-CCM+ to run sequentially with Simcenter STAR-CCM+ leading the co-simulation.; Concurrent: sets Abaqus and Simcenter STAR-CCM+ to run simultaneously during the co-simulation. Only available if the coupling scheme is set to explicit.

Write Abaqus Keywords: When activated, instructs Simcenter STAR-CCM+ to automatically add co-simulation definitions to the Abaqus *.inp file, based on the co-simulation set up in Simcenter STAR-CCM+. Simcenter STAR-CCM+ overwrites any existing *CO-SIMULATION keywords defined in the *.inp file. When deactivated, you must manually add the co-simulation parameters to the *.inp file.

Abaqus Execution: Allows you to specify the options for launching and running the Abaqus job. The available properties are:; Input File -- Specifies the Abaqus input file for the co-simulation. You can enter either the full path to the file or a path relative to the Simcenter STAR-CCM+ simulation file. You can specify the relative path only if the Abaqus input file is located in the same directory as the Simcenter STAR-CCM+ simulation file. When running Abaqus through a remote connection, you can specify the Abaqus input file path to the location on the remote connection as absolute, /RemoteConnectionDirectory/[AbqFileName].inp.; Executable Name -- Specifies the command to run Abaqus. If you set up a shortcut to run Abaqus in batch, you can enter the shortcut. Otherwise, specify the path to the Abaqus executable, including the executable name.; Additional Command Line Options -- Specifies more command line options for use with the Abaqus executable. Multiple options must be space-separated. Make sure that the command options are compatible with the co-simulation analysis mode. For example, entering -double both -output_precision full -user usersub.f would run Abaqus/Explicit in double precision, output results to the output database (*.odb) file in double precision, and specify a user subroutine to be used in the analysis.; Number of CPUs -- Specifies the number of processors that Abaqus uses when the co-simulation is run. Must be entered as an integer. If the number of processes for Abaqus is entered using the command-line argument, -np, this property is ignored.; Host List -- Specifies the hosts and CPUs per host on which Abaqus is run (for example, host1:2,host2:4).; Remote Shell -- Specifies the type of shell that is used to log in to the remote machine. It is recommended that you use the default, rsh, for unsecured networks (usually within a firewall). The other supported option is ssh, and must be used when all connections are secure (for example, when rsh is blocked). If using ssh, make sure that you set it up so that it does not prompt for a password.; Remote User -- Specifies the username for the remote shell login. If this option is left blank, the local username is used.

Abaqus Library: Allows you to specify the absolute path for the abaqus library.

External Code Units Manager: To specify the units for data that is imported from and exported to Abaqus, use the [Link 1] > Values > External Code Units Manager node. For imported fields, the unit specifications tell Simcenter STAR-CCM+ the units of the incoming data. For exported fields, the unit specifications ensure that data sent to Abaqus is in the correct units. In each case, these settings depend on which consistent unit system was used when defining the Abaqus model. These settings do not affect the units that are used in Simcenter STAR-CCM+ calculations.; If a unit used in the Abaqus model is not a pre-defined unit in the Simcenter STAR-CCM+ units manager, you must create the unit before it appears and can be selected in the child nodes of the External Code Units Manager node.

Partner Job Name: Defines the current arbitrary job name for the Abaqus Co-Simulation output files. When setting up a co-simulation restart, the Partner Job Name must be different from the Old Job Name. See Restarting from a Previous Abaqus Simulation.

Partner Timeout: Allows you to specify the maximum time Simcenter STAR-CCM+ will wait for the Abaqus partner operations.

Inner Iterations Per Exchange (For Implicit Coupling Only): Specifies the number of inner iterations between data exchanges within a time-step.

Minimum Number of Exchanges (For Implicit Coupling Only): Specifies the minimum number of exchanges that are performed within a time-step.

Link Right-Click Actions

Create New Zone: Allows you to create a new zone within an existing link.

Create SIMULIA CSS XML File: Allows you to export a SIMULIA CSS XML file for the co-simulation. For the Do Not Launch launch partner option an *.xml file is needed to run the co-simulation. Only available when Launch Partner Option is set to Do Not Launch.
Write Abaqus Keywords...: When activated, instructs Simcenter STAR-CCM+ to automatically add co-simulation definitions to the Abaqus *.inp file, based on the co-simulation set up in Simcenter STAR-CCM+. Simcenter STAR-CCM+ overwrites any existing *CO-SIMULATION keywords defined in the *.inp file. Only available when Launch Partner Option is set to Do Not Launch
Terminate: Closes the connection between Simcenter STAR-CCM+ and Abaqus.