In a two-way transfer FSI analysis, the CFD analysis results (forces, temperatures, heat flows, or heat transfer coefficients and near wall temperatures) at the fluid-structure interface are transferred to the Mechanical model and applied as loads. Within the same analysis, the subsequently calculated displacements, temperatures, or heat flows at the fluid-structure interface are transferred back to the CFD analysis. Two-way transfer is appropriate when displacements and temperature differentials calculated in Mechanical are large enough to have a significant effect on the fluid analysis.

Because of the two-way interaction between the two analyses, the analyses are looped through repeatedly until overall equilibrium is reached between the Mechanical application solution and CFD solution. Two-way FSI is supported between Mechanical and Fluent and Mechanical and CFX. In either case, you set up the static or transient structural portion of the analysis in the Mechanical application, including defining one or more fluid-structure interface boundary conditions. You continue the analysis in Fluent or CFX, and view the structural results in the Mechanical application.

For general information on two-way FSI, see System Coupling. For more information on two-way FSI using Mechanical and Fluent, see Performing System Coupling Simulations Using Fluent in the Fluent User's Guide. For more information on two-way FSI using Mechanical and CFX, see Coupling CFX to an External Solver: System Coupling Simulations in the CFX-Solver Modeling Guide.