  Rayleigh-Benard convection is not only a classical problem in fluid dynamics
but plays also an important role in many metallurgical and crystal growth
applications. The measurement of the flow field and of the dynamics of the
emerging large-scale circulation in liquid metals is a challenging task due to
the opaqueness and the high temperature of the melts. Contactless inductive
flow tomography is a technique to visualize the mean three-dimensional flow
structure in liquid metals by measuring the flow induced magnetic field
perturbations under the influence of one or several applied magnetic fields. In
this paper, we present first measurements of the flow induced magnetic field in
a Rayleigh-Benard setup, which are also used to investigate the dynamics of the
large-scale circulation. Additionally, we investigate numerically the quality
of the reconstruction of the three-dimensional flow field for different sensor
configurations.
