Viscoelastic Computations of Polymeric Wire-coating Flows

This study considers both a single and multi-mode viscoelastic analysis for wirecoating ows. The numerical simulations utilise a nite element time-stepping technique, a Taylor-Petrov-Galerkin/pressure-correction scheme employing both coupled and decoupled procedures between stress and kinematic elds. An exponential Phan-Thien/Tanner model is used to predict pressure-drop and residual stress for this process. Rheometrical data tting is performed for steady shear and pure extensional ows, considering both high and low density polyethylene melts. Simulations are conducted to match experimental pressure-drop/ owrate data for a contraction ow. Then, for a complex industrial wire-coating ow, stress and pressure drop are predicted numerically and quanti ed. The bene ts are extolled of the use of a multi-mode model that can incorporate a wide-range discrete relaxation spectrum to represent ow response in complex settings. Contrast is made between LDPE and HDPE polymers, and dependency on individual relaxation modes is identi ed in its contribution to overall ow behaviour.