Fluctuating hydrodynamics approach to dilute polymer solutions. I. Solvent velocity correlations and weak flow

摘要

We study solvent dynamics in a solution consisting of polymers and solvent. Our starting point is a system of Langevin equations where the solvent velocity field and solvent velocity fluctuations are explicitly included. We calculate the Fourier transform of the solvent velocity autocorrelation function in the dilute regime. From this correlation function we calculate the dynamic viscosity of the solution and obtain an effective equation of motion of the solvent which turns out to be the generalized Maxwell model of a linear viscoelastic fluid.