Dynamo action driven by convection: the influence of magnetic boundary conditions

We study the influence of different magnetic boundary conditions on the gen eration of magnetic fields by turbulent convection. It is found that the st ructure and strength of the generated field in the vicinity of the boundary is strongly dependent on the choice of boundary conditions. In the convect ive interior, however, the solutions remain largely insensitive to the boun dary conditions. In all cases the overall efficiency of the dynamo process remains high with a steady state magnetic energy density between 12 and 25 per cent of the turbulent kinetic energy, and peak field values exceeding t he equipartition level. These results support the idea that the solar granu lation may constitute a dynamo source for magnetic fields in the quiet phot osphere.