Microscopic models of complex fluids in nonequilibrium
نویسندگان
چکیده
The method of nonequilibrium molecular dynamics (NEMD) is used to simulate microscopic models of macromolecular fluids in flow situations. Procedures to extract rheological properties, such as the (non-newtonian) viscosity, normal pressure differences as well as information on flow induced structural changes, are discussed. This contribution focusses on polymer melts and polymer solutions, liquid crystalline polymers as well as wormlike micellar systems under shearand elongational flows. Both the anisotropy of the viscosity and the nonlinear flow behavior are of interest in those systems and can be compared well with experimental results on neutron scattering, flow birefringence and rheological measurements. Investigations on the underlying structural changes during the NEMD simulations allow the rheological response to be interpreted based on molecular mechanisms.
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