Dynamics of a Linear Polymer in a Creeping Flow

An understanding of the dynamics of nanofluids, such as polymer laden fluids, could be used to design the technology for high throughput molecular analysis and manipulation. In this study we simulate the motion of a linear polymer advected by a fluid in a rectangular microchannel. We consider the creeping laminar flow regime, ie with zero Reynolds number. The polymer is modelled as a chain of beads connected by elastic springs. The dynamics of this nonlinear mechanical system is studied as a function of model parameters, including the spring equilibrium distance, the mass of a bead, the spring constant and the fluid pressure gradient. It is found that the interaction of the polymer with the shear flow introduces not only a stretching of the chain, but also a splitting in its fundamental vibration energy levels.