In this study we have constructed and tested 3D numerical model of the Virgo cluster, the core of which is thermally supported by the bubbles produced by the active galactic nucleus of the central galaxy.

The physical properties of the plasma (intracluster medium, ICM) are not precisely known. Usually the ICM models use the values of thermal diffusivity and kinematic viscosity calculated in the classical work of Spitzer [10] (see also review by M. Ruszkowski in this volume). It is accepted, however, that magnetic fields decrease the diffusivity, since they suppress movements of charged particles across the field lines. The same is believed to be true for the value of the viscosity as well. Usually a fraction of the Spitzer value is used to approximate thermal diffusivity of the ICM [3, 6], which assumes chaotic orientation of magnetic field lines (i.e., magnetic field lines are bent on scales smaller than the mean free path of an electron in the plasma).

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