About Interactions

I/O-to-I/O connections require additional information to fully specify the exchange of field output quantities during simulation; for example, whether displacement output variables or temperature variables are exchanged (or both). Interactions provide this additional information and have a 1-to-1 association with an I/O-to-I/O connection.

Interaction connections between I/O ports are more general-purpose than scalar variable connections between output and input ports. You can define multiple field quantities that pass through an interaction.

For example, a fluid-structure interaction (FSI) is commonly simulated by the exchange of specific work-conjugate variable pairs such as velocity and traction fields.

The five types of interactions are described below.

Fluid-Structure Interaction (FSI)

FSI simulates the motion and behavior of a fluid (or gas) and its effect on a solid, and vice versa. The fluid flow might cause deformation in a solid, while the deformation might alter the fluid flow around the solid. You can use an FSI interaction to solve fluid-structure interaction problems between Abaqus/Standard or Abaqus/Explicit and the Fluid Scenario Creation app (CFD flow solver).

For FSI implicit coupling, the fluid solver leads the coupling. The CFD flow solver and the structural solver exchange displacement data, and the CFD flow solver extrapolates velocity data from the displacement data. As the co-simulation proceeds, the CFD flow solver writes FSI relaxation, FSI relative residual, and FSI absolute residual data to the status (.sta) file. The solver also performs two convergence checks: the relative residual and the absolute residual.

Conjugate Heat Transfer (CHT)

CHT simulates the convective heat transfer between a solid and a fluid (or gas). As the fluid flows around the solid, heat might be added to or removed from the solid thus heating or cooling the solid. In return this might affect the ambient fluid temperature and subsequently the amount of heat added/removed to/from the solid. CHT couples Abaqus/Standard or Abaqus/Explicit with the Fluid Scenario Creation app (CFD flow solver).

One example of this type of co-simulation is the heat transfer between an electronic chip on a circuit board and the ambient air flowing around it for cooling.

Induction Heat Transfer (IHT)

IHT simulates the interaction between heat generated in a part by electromagnetic induction and the thermomechanical behavior of that part. The electromagnetic induction is modeled accurately by the CST Studio Suite^® solver.

Standard-Explicit Subcycle (SXS)

This type of structure-to-structure interaction couples the Abaqus/Standard (implicit dynamics) solver with the Abaqus/Explicit solver (through the use of an explicit dynamic step in the Mechanical Scenario Creation app).

This option uses a specialized coupling algorithm called "GandC" to account for the varying stable time increment size between implicit and explicit dynamics and to effectively and robustly solve problems. In this algorithm Abaqus/Explicit might take one or more increments between each Abaqus/Standard increment. This option is the preferred method of solving a structure-to-structure co-simulation.

Standard-Explicit Lockstep (SXL)

This type of structure-to-structure interaction couples the Abaqus/Standard (implicit dynamic) solver with the Abaqus/Explicit solver (through the use of an explicit dynamic step in the Mechanical Scenario Creation app).

This option is a weaker coupling algorithm in which Abaqus/Standard takes step sizes dictated by the Abaqus/Explicit stability limit.