Rheodynamics of extrusion of viscous compressible materials

Consideration is given to the processes of compression and flow of viscous compressible materials when being forced out of a chamber via a slot to a guide gauge. The analytical solution of the problem obtained in the Lagrangian coordinate allows determination of density, velocity and stress distributions in a sample and in a pressed-out rod. It is found that the principal dimensionless parameters are the extrusion time to compression time ratio and dimensionless slot drag. Different compression regimes are analysed and conditions of their realization are obtained.