Circulatory high-viscosity non-Newtonian fluid flow in a single-screw extruder channel

This paper is devoted to definition of a width-to-depth ratio of a single-screw extruder channel when sidewalls do not affect the velocity profiles of circulatory high-viscosity non-Newtonian fluid flow at the mid of the channel. The channel has a rectangular cross-section. Power-law model is used to describe fluid behavior. The indirect boundary element method is used for numerical solution taking into account of sidewalls. Comparing of obtained velocity profiles with the known results showed a good agreement. Research is performed in the range of power-law index from 0.4 to 1.0. The method for obtaining the velocity component profiles for the case of shear-thinning fluid flow without considering influence of sidewalls is presented. The width-todepth ratio of a single-screw extruder channel when it is acceptable to neglect influence of sidewalls on flow at the mid of the channel is defined.