Molecular dynamics simulation of planar Poiseuille flow for polymer melts in atomically flat nanoscale channel

Abstract

Molecular dynamics simulation (MDS) is carried out using finitely extensible nonlinear elastic (FENE) chains to investigate the Poiseuille flow of polymer melt in atomically flat nanoscale channel. The influences of external force, wall–fluid interacting parameter and chain length on flow behavior are studied. The simulations show that the external force and the wall–fluid interacting parameters have much influence on the flow velocity profiles, and the wall–fluid interacting parameter has much influence on the distribution of polymer chains between walls. The larger external force and weaker wall–fluid interaction can promote polymer melt to flow with larger boundary velocity and maximum velocity. The larger external force, the weaker wall–fluid interaction and the longer polymer chains can improve the diffusion capacity of polymer melts. The external force and the chain length have much influence on the polymer structure, the gyration radius and the alignment tensor of polymer chains. The larger external force and longer polymer chains can help polymer melts to form the orientation in x-direction. At the boundaries, the sticking and the dragging phenomena occur, the sticking phenomenon confines the diffusion of polymer melt, the dragging phenomenon can promote the polymer diffusion contrarily.