Analysis and simulation of thermal / viscose model for Melt Spinning process

The Melt Spinning process is used for thin ribbons manufacture of amorphous materials and nanocrystalline. The material in liquid state is injected through a nozzle and solidifies upon contact with a copper rotating wheel. In this work, we intend to find, by means of a computer simulation with OpenFOAM (R), a thermal profile of the material from its ejection through the nozzle to the conformation of the ribbon itself. A two-phase model of the Volume of Fluids (VOF) type is used. Although neither of the two fluids (molten metal and air) can be considered compressible for working pressures, a resolution method of a compressible nature is used. This allows to represent the density changes in the air due to temperature changes, and to define a thermo-physical model for the specific alloy. For this, we considered an alloy of constant thermal conductivity, specific heat and density. The phase change is represented by a model that relates viscosity (mu) with temperature (T) in which the viscosity increases several orders of magnitude when the material passes below the crystallization temperature. Among the options of viscous models offered by OpenFOAM (R), we select a polynomial model whose coefficients were determined by OCTAVE routines until achieving a fitting curve [1] for the viscosity within the temperature range of 600 to 1700 degrees C.