题目：The dynamics of flexible and Brownian filaments in viscous flows

报告人：刘亚楠 博士 （PMMH，ESPCI ParisTech，France）

时间地点：2018年10月15日（周一） 13 :00，物理学院856教室

报告摘要：

The morphological dynamics, instabilities and transitions of elastic filaments in viscous flows

underlie a wealth of biophysical processes, and are also key to deciphering the rheological behavior

of many complex fluids and soft materials. Here, we combine experiments with actin filaments as

an experimental model system and computational modeling with non-local slender body theory to

elucidate the dynamical regimes and morphological transitions of elastic Brownian filaments in a

simple shear ow. The filament dynamics and transitions are primarily governed by a dimension-

less elasto-viscous number comparing viscous drag forces to elastic bending forces, with thermal

fluctuations only playing a secondary role. The transitions are characterized by a buckling instability and the appearance of localized high-curvature bends that propagate along the filaments in

apparent snaking motions. We present a complete characterization of filament morphologies and

transitions as a function of elasto-viscous number and scaled persistence length and demonstrate

excellent agreement between theory, experiments and simulations.

合作者：Brato Chakrabarti, David Saintillan （University of California San Diego, USA）;

                  Olivia Du Roure, Anke Lindner （ESPCI, CNRS, France）.