Adaptively refined large eddy simulations of a galaxy cluster: turbulence modeling and the physics of the intracluster medium.
We present a numerical scheme for modeling unresolved turbulence in cosmological adaptive mesh refinement
codes. As a first application, we study the evolution of turbulence in the intracluster medium (ICM) and in
the core of a galaxy cluster. Simulations with and without subgrid scale (SGS) model are compared in detail.
Since the flow in the ICM is subsonic, the global turbulent energy contribution at the unresolved length scales
is smaller than 1% of the internal energy. We find that the production of turbulence is closely correlated with
merger events occurring in the cluster environment, and its dissipation locally affects the cluster energy budget.
Because of this additional source of dissipation, the core temperature is larger and the density is smaller in
the presence of SGS turbulence than in the standard adiabatic run, resulting in a higher entropy core value.
Maier, A., Iapichino, L., Schmidt, W., & Niemeyer, J. C.
The Astrophysical Journal 707.1 (2009): 40.