Abstract We carried out 3D time-dependent numerical simulations using the software package STHAMAS3D to get some basic understanding of the role of melt convection on the crucible dissolution rate, measured as the whole mass of dopant originated from the crucible which can be found in the melt after a given period of time. It was found that melt convection has a strong influence on the dissolution rate: the dissolution rate strongly increases when the melt convection is present. Furthermore the influence of the diffusion coefficients on dissolution rate was also studied. The simulations show that the dissolution rate strongly increases with the increasing of the diffusion coefficient. Therefore it is mandatory to have accurate measurements of diffusion coefficients.