Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

CPP: Fachverband Chemische Physik und Polymerphysik

CPP 7: POSTERS Rheology

CPP 7.1: Poster

Montag, 25. Februar 2008, 16:45–19:00, Poster A

Spatio-temporal behavior of dipolar nano-rods under shear — •Sebastian Heidenreich, Siegfried Hess, and Sabine H. L. Klapp — Institut für Theoretische Physik, Technische Universität Berlin, Hardenbergst. 36, D-10623

The flow properties of nano-rods are strongly affected by the dynamical behavior of molecular alignment. A theoretical description can be made by an relaxation equation [1] of the order parameter tensor. For plane Couette flow geometry the model leads to a rather complex orientational and flow behavior [2]. Depending on the model parameters and the boundary conditions various flows like shear banding flow can occur. To describe suspensions consisting of dipolar nano-rods that can form clusters with an effective polarization the relaxation equation has to be extended. In [4] the coupling of the orientation and the dipole moment was investigated for the bulk system. The additional dipole moment strongly affects the orientational dynamics. In this contribution we study a spatially inhomogeneous tensor model. In the plane Couette geometry structure emerges in the flow profile not known from the flow behavior of nano-rods without dipole moments. Furthermore, we present the effect of the dipole moment on the start up flow dynamics of shear bands.
S. Hess, Z. Naturforsch. 30a, 728, 1224 (1975)
B. Chakrabarti, M. Das, C. Dasgupta, S. Ramaswamy, and A. K. Sood, Phys. Rev. Lett. 92, 055501,(2004);
S. Grandner, S. Heidenreich, P. Ilg S. H. L. Klapp, and S. Hess; S. Grandner, S. Heidenreich, S. Hess, and S. H. L. Klapp, EPJE in press