Numerical Study of Residual Stresses Due to External Cooling in Extruded Polymer Profiles

Profile extrusion is a production technique to make polymer profiles and hollow tubes. At certain distance after the die exit extrudate guided into cooling chamber, where cooled extensively set part dimensions. Uniform in chamber required avoid warpage twisting of due differential shrinkage. The effect on shape residual stresses final product are numerically studied. Two different cases studied: 2D axisymmetric problem viscoelastic fluid exiting an annular 3D square shaped die. from L c $L_{\text{c}}$ exit. Extrudate modeled by subjecting heat loss via convection. For < z ≤ $L_{\text{die}} $z>L_{\text{c}}$ varied mimic speeds. Weissenberg Wi, this work. Results show that for high values Wi significant skin-effect appear near edges numbers small . It also shown significantly altered swell, when slower. fast , does not have time relax elastic “frozen in.” This leads less swell but large edges.