  FEARLESS (Fluid mEchanics with Adaptively Refined Large Eddy SimulationS) is
a numerical scheme for modelling subgrid-scale turbulence in cosmological
adaptive mesh refinement simulations. In this contribution, the main features
of this tool will be outlined. We discuss the application of this method to
cosmological simulations of the large-scale structure. The simulations show
that the production of turbulence has a different redshift dependence in the
intra-cluster medium and the warm-hot intergalactic medium, caused by the
distinct stirring mechanisms (mergers and shock interactions) acting in them.
Some properties of the non-thermal pressure support in the two baryon phases
are also described.
