The behavior of confined polymer melts in shear flow is of importance in several practical applications such as lubrication and polymer processing. For example, an important consideration in polymer extrusion operations is the surface finish of the extrudate, which is governed largely by the flow behavior at the polymer-wall interface. There is therefore considerable interest in establishing a cause-effect relationship between polymer-surface interactions and melt flow behaviour.

In collaboration with Professor Juan de Pablo in chemical engineering we have recently developed an algorithm for the simulation of liquids undergoing shear flow. The fluid is confined between two walls that are set in motion. The simulation cell (with only one of the chains shown) looks like this: