Numerical simulation of bi-disperse polymer flow in complex geometries using Rolie–Double–Poly model within OpenFOAM software

Modeling the behavior of bi-disperse, linearly entangled polymers blends using the Rolie–Double–Poly constitutive equation is essential for understanding the reliability of the model in simulating complex flow behaviors. This study examines the extensional response of polymer blends, particularly the stretching of chains under pure extensional flow along the centre-line in two flow geometries: hyperbolic contraction flow and cross-slot flow with hyperbolic corners. Coupled and uncoupled models were implemented within the OpenFOAM software via the \texttt{RheoTool} toolbox where the simulations use the rheoFoam solver to model incompressible viscoelastic fluid flow. The effect including the contraction lengths, blend composition of chain lengths, and chain coupling are the key factors in this studies. One significant results reveal that the Rolie–Double–Poly model more accurately captures the extensional behavior of polymer chains compared to the uncoupled model underscoring its potential applicability for more complex, polydisperse systems.