Rheological properties of polymer dumbbell models with configuration-dependent anisotropic friction

Abstract

With the help of Brownian dynamics simulations we study the rheological properties of polymer Hookean dumbbell models with anisotropic friction. The friction tensor depends on the actual configuration of the dumbbell. The resulting equation of motion is a Langevin equation with multiplicative noise. The correlations of the ‘‘Langevin’’ Brownian forces appearing in this equation turn out to be anisotropic, too. They should be carefully distinguished from the ‘‘smoothed out’’ Brownian forces which appear in the standard derivations of the Fokker–Planck equation in kinetic theory. We will discuss the rheological properties in steady shear flow for two different friction tensors.