Brownian configuration fields: a new method for simulating viscoelastic flow

In this paper a new method for calculating viscoelastic fluidflows is presented. The polymer stress is not calculated from a closedform constitutive equation but from a microscopic model. Instead ofconsidering the motion of individual molecules we calculate the evolutionof an ensemble of configuration fields, representing the internal degreesof freedom of a model molecule. The configuration fields are deformedand convected by the flow and are exposed to thermal motion. The fielddescription is incorporated in a finite element calculation of the flow fieldwhere the stress in the fluid is now obtained from an average taken overall the configuration fields. The results for flow past a cylinder for aHookean dumbbell suspension will be compared with the results obtainedfrom a fully macroscopic calculation o! f the equivalent Oldroyd-B model.Excellent agreement is obtained.