Leading topic of this article is description of Lorentz forces in the container with cuboid shape. Inside of the container is an electrically conductive melt. This melt is driven by rotating magnetic field. Numerical simulations of these unsteady flows were performed in commercial sofrware Ansys Fluent (version 13). Input data (Lorentz forces in the container with cuboid shape) were also obtained from the computing program NS-FEM3D, which uses DDES method of computing as a turbulent approach. Related velocity field of the melt inside the container was displayed and described as well. and Obsahuje seznam literatury