A monolithic approach to fluid-structure interactions based on the space-time
finite element method (STFEM) is presented. The method is applied to the investigation
of stress states in silos filled with granular material during discharge. The thin-walled siloshell
is modeled in a continuum approach as elastic solid material, whereas the flowing
granular material is described by an enhanced viscoplastic non-Newtonian fluid model.
The weak forms of the governing equations are discretized by STFEM for both solid and
fluid domain. To adapt the matching mesh nodes of the fluid domain to the structural
deformations, a mesh-moving scheme using a neo-Hookean pseudo-solid is applied. The
finite element approximation of non-smooth solution characteristics is enhanced by the
extended finite element method (XFEM). The proposed methodology is applied to the
4D (space-time) investigation of deformation-dependent loading conditions during silo
discharge