FEATool Multiphysics™ 1.11 FEATool Multiphysics release 1.11 is now available and extends the multi-simulation solver concept even further by introducing a fluid-structure interaction (FSI) solver (in addition to the existing built-in multiphysics, OpenFOAM, and FEniCS solver integrations). The following new features are available with FEATool Multiphysics 1.11.Fluid-Structure Interaction (FSI) FEATool now features a built-in FSI physics mode and dedicated FSI solver to make fluid-structure interaction simulations easy to set-up directly from both the GUI and optional command line interface.