  The hydrodynamics of viscoelastic materials (for example polymer melts and
solutions) presents interesting and complex phenomena, for example
instabilities and turbulent flow at very low Reynolds numbers due to normal
stress effects and the existence of a finite stress relaxation time. This
present work is motivated by renewed interest in instabilities in polymer flow.
The majority of currently used numerical methods discretize a constitutive
equation on a grid with finite difference or similar methods. We present work
in progress in which we simulate viscoelastic flow with dissipative particle
dynamics. The advantage of this approach is that many of the numerical
instabilities of conventional methods can be avoided, and that the model gives
clear physical insight into the origins of many viscoelastic flow
instabilities.
