Abstract: Based on the incompressible smoothed particle hydrodynamics (ISPH) method, a program written in FORTRAN language was developed to simulate three-dimensional non-Newtonian flow. The efficiency of numerical schemes is evaluated by simulating a planar Poiseuille flow. It is pointed out that in the simulation of non-Newtonian flow, the mirror particle boundary treatment of the wall boundary is more suitable than the dummy particle boundary. A single screw extruder three-dimensional flow is calculated using this algorithm. Two types of inflow and outflow boundary implementation schemes including periodic boundary and pressure boundary are elaborated. The results show that the periodic boundary is more feasible than pressure boundary; the algorithm is accurate and fast if an appropriate number of particles is selected; circumfluence form in the cross-section of the groove; shear stress gradient is more concentrated in the top left angle and right angle; the flow along the spiral groove is stable, with the increase of the reverse pressure gradient, the flow bear more resistance. This research laid the foundation for simulating more complex three-dimensional screw extrusion using ISPH method.

Key words: Incompressible smoothed particle hydrodynamics, Non-Newtonian fluid, Single screw extruder, Three-dimensional flow