Europhys. Lett., 60 (2) , pp. 181-187 (2002)
Dumb-bell model for polymer transport in laminar flowsM. De Lucia1, A. Mazzino2, 3 and A. Vulpiani1
1 Dipartimento di Fisica, and Istituto Nazionale di Fisica della Materia (UdR and SMC), Università di Roma "La Sapienza" Piazzale Aldo Moro 2, I-00185 Roma, Italy
2 ISAC/CNR, Sezione di Lecce - Strada provinciale Lecce-Monteroni km 1.2 I-73100 Lecce, Italy
3 INFM-Dipartimento di Fisica, Università di Genova - I-16146 Genova, Italy
(Received 30 April 2002; accepted in final form 26 July 2002)
Polymer transport is investigated, in the limit of the so-called dumb-bell model, for two paradigmatic laminar flows having open and closed streamlines, respectively. For both types of flows we find transport depletion owing to the action of the polymers elastic degree of freedom. For flows with closed streamlines the leading mechanism for the observed transport reduction is the (dynamical) formation of barriers. For flows with open streamlines the reduction of transport is induced by the renormalization of the bare diffusion coefficient. Results have been obtained by means of Lagrangian simulations.
05.60.-k - Transport processes.
© EDP Sciences 2002