  We present a phenomenological model of the dynamics of buoyant bubbles in the
atmosphere of a cluster of galaxies. The derived equations describe velocity,
size, mass, temperature and density of the buoyant bubbles as functions of time
based on several simple approximations. The constructed model is then used to
interpret results of a numerical experiment of heating of the cluster core with
buoyant bubbles in a hydrodynamical approximation (i.e. in the absence of
magnetic fields, viscosity, and thermal diffusion). Based on the model
parameters we discuss possible limitations of the numerical treatment of the
problem, and highlight the main physical processes that govern the dynamics of
bubbles in the intracluster medium.
