Application of the PTT Model for Capillary Extrusion of Rubber Compounds

Rubber compounds have high viscoelastic property. One of the viscoelastic behaviors shown in profile extrusion is an extrudate swell and circulation flow at the corner of inside of die. Application. of viscoelastic model to a capillary extrusion has beets investigated in this study. Experiments and simulations have been performed using Fluidity Tester and commercial computational fluid dynamics (CFD) code, Polyflow respectively. Die swell of rubber compounds in a capillary die were predicted using a non-linear differential viscoelastic model, Phan-Thien and Tanner (PTT) model for various relaxation tunes and relaxation modes. As relaxation time and number of relaxation anode increase, die swell increases. The results of simulations were compared with the experiment. Pressure and velocity distributions, and circulation flows at the corner of reservoir have been analyzed through computer simulation. Two and three: relaxation modes with large range of relaxation time examined in this study showed good agreement with experimental results of die swell and well represented circulation flow at the corner of reservoir in the capillary die.Mullner HW, 2007, POLYM TEST, V26, P1041, DOI 10.1016/j.polymertesting.2007.07.003Liang JZ, 2007, J APPL POLYM SCI, V104, P70, DOI 10.1002/app.25506MULLNER HW, 2006, PAMM, V6, P575Tanner RI, 2005, J NON-NEWTON FLUID, V129, P85, DOI 10.1016/j.jnnfm.2005.05.010Sombatsompop N, 2004, POLYM ADVAN TECHNOL, V15, P472, DOI 10.1002/pat.490Huang JC, 2003, J APPL POLYM SCI, V87, P1587, DOI 10.1002/app.11499*FLUENT INC, 2003, POL 3 10Sombatsompop N, 2002, J APPL POLYM SCI, V86, P1762, DOI 10.1002/app.11212Huang JC, 2002, J APPL POLYM SCI, V84, P1269, DOI 10.1002/app.10466Ngamaramvaranggul V, 2002, INT J NUMER METH FL, V38, P677, DOI 10.1002/fld.237Sombatsompop N, 2001, J APPL POLYM SCI, V82, P2525Ngamaramvaranggul V, 2001, INT J NUMER METH FL, V36, P539, DOI 10.1002/fld.145Liang JZ, 2001, POLYM TEST, V20, P29TANNER RI, 2000, ENG RHEOLOGYGast L, 1999, INT J NUMER METH FL, V29, P1Gifford WA, 1998, POLYM ENG SCI, V38, P1167WHITE JL, 1995, RUBBER PROCESSING TEMACOSKO CW, 1994, RHEOLOGY PRINCIPLESMONTES S, 1993, J NON-NEWTON FLUID, V49, P277WHITE JL, 1990, PRINCIPLES POLYM ENGHUNEAULT MA, 1989, PLAST ENG, V9, P39YANG B, 1987, POLYM ENG SCI, V27, P1088BIRD RB, 1987, DYNAMICS POLYM LIQUI, V1TOKITA N, 1981, RUBBER CHEM TECHNOL, V54, P439VLACHOPOULOS J, 1978, RUBBER CHEM TECHNOL, V51, P133AGARWAL PK, 1978, POLYM ENG SCI, V18, P282PHANTHIEN N, 1977, J NONNEWTONIAN FLUID, V2, P353HAN CD, 1976, RHEOLOGY POLYM PROCE