Adaptive configuration fields: a new multiscale simulation technique for reptation-based models with a stochastic strain measure and local variations of life span distribution

Abstract

In this work a new multiscale simulation technique, i.e. Adaptive configuration fields method (ACFM), has been proposed for complex flow simulation of state-of-the-art reptation-based models for entangled polymeric systems. Specifically, this technique combines the essential aspects of the previously introduced Brownian configuration fields and the deformation fields methods [J. Non-Newtonian Fluid Mech. 70 (1997) 79; J. Non-Newtonian Fluid Mech. 89 (2000) 209] to allow simulation of advanced reptation models with a stochastic strain measure and local variations of life span distribution. In order to examine the fidelity and robustness of our new simulation technique, we have performed simulations in a number of different fixed kinematics flows using the single segment reptation model of Öttinger [J. Rheol. 44 (2000) 1293], which possesses the essential features required for quantitatively describing the non-linear rheology of polymer melts, but cannot be implemented in a complex flow using the available state-of-the-art Eulerian multiscale simulation techniques, namely, the Brownian configuration fields or the deformation fields. In turn, the simulation results in unidirectional flows are compared with pure Brownian dynamics simulations and it is shown that the results are in excellent agreement, thus verifying the accuracy of the adaptive configuration fields method.