Numerical Simulation of Gas-Assisted Extrusion of Four-Lumen Micro-Catheter based on FEM Method

Abstract

In this work, the gas-assisted extrusion of four-lumen micro-catheter (FLMC) was numerically studied by computed fluid dynamics (CFD) software software Polyflow. The extrudate profiles and die swell ratios of FLMC for the gas-assisted extrusion are gotten, and compared with those of the traditional extrusion. Results show that the die swell of FLMC is eliminated by the gas-assisted extrusion. To analyze the effects of gas-assisted on the elimination of die swell, the flow velocities, pressure, shear stress, and the first normal stress difference distributions of melt were obtained for both extrusions. Results show that compared with the results of traditional extrusion, the radial velocities, pressure, shear stress and the first normal stress difference of FLMC for the gas-assisted extrusion are very little, and the axial flow velocity of melt is uniform, which can reduce the elastic energy storage and finally eliminate the die swell problem.