Modelling massive forming processes with thermally coupled fluid dynamics

Schmitter, E.D.
University of Applied Sciences Osnabrueck

With massive forming processes like rolling, extrusion and friction stir welding metal alloys are deformed in a hot solid state. Material flow under ideally plastic conditions can be modelled with computational fluid dynamics (CFD). This approach has advantages especially in case of large deformations.

Material properties enter via a viscosity function, that can be related to the flow stress kf, locally depending on forming velocity and temperature. Internal friction of the moving material acts as a heat source, so that a fully coupled nonlinear problem arises, that in this approach is solved using the incompressible Navier-Stokes equations and the convective heat equation.