Modeling the rheology of polymer solutions by dissipative particle dynamics

Dissipative particle dynamics (DPD), a new simulation technique that focuses on intermediate time and length scales, is evaluated for systems in which polymers are used as viscosity index improvers. Model studies of simple non-Newtonian fluids show that DPD reveals the expected shear thinning. DPD solutions confined between solid surfaces, predict anisotropic conformational relaxation dynamics. In addition, the effects of thermodynamic solvent quality on the configurations and rheological behavior of dissolved polymers, essential to the performance of multigrade lubricants, are represented by the DPD model.