Brownian dynamics simulations of bead-rod-chain in simple shear flow and elongational flow

We have simulated a dilute polymer solution under simple shear and elongational flows using the bead-rod-chain model, by incorporating intra-chain hydrodynamic interaction and excluded volume effects. Configurational properties and theological quantities were calculated. For the simple shear flow. shear rate dependencies of chain's size, shape, and rotation were monitored. Shear-thinning was observed at all shear rates. In addition, the critical strain rate, epsilon(c), at which the polymer undergoes a coil-stretch transition under elongational flow, was investigated. The slope at the inflection point of the log(R-g(2)) vs log(epsilon) curve increased as the chain length increased, indicating a possible first order transition, in agreement with theories and experiments. (C) 2003 Published by Elsevier Ltd.