POLYMER-CHAINS IN RANDOM LAYERED FLOWS - A SCALING APPROACH

We consider the diffusion of a polymer chain in random layered flows. We use scaling ideas and take the randomness of the flow into account through an Imry-Ma-type argument. For the chain's dynamics both the Zi mm approach for screened hydrodynamic interactions and also the Rouse approach are considered. We compute both the internal dynamics of the chain (motion of a segment) and also the center of mass motion; for th e Rouse model we recover the exact results obtained by Oshanin and Blu men. The polymer's dynamics at long times turns out to be diffusive or enhanced, depending on the flow's disorder (thread-like or layer-like ), and on the hydrodynamic interactions. Furthermore we also evaluate the chain's conformations under these conditions.