Work

Effects of thermal noise on the transitional dynamics of an inextensible elastic filament in stagnation flow

Year: 2015

Type: article

Abstract: We investigate the dynamics of a single inextensible elastic filament subject to anisotropic friction in a viscous stagnation-point flow, by employing both a continuum model represented by Langevin type stochastic partial differential equations (SPDEs) and a dissipative particle dynamics (DPD) method. Unlike previous works, the filament is free to rotate and the tension along the filament is determined by the local inextensible constraint. The kinematics of the filament is recorded and studied with normal modes analysis. The results show that the filament displays an instability induced by negative tension, which is analogous to Euler buckling of a beam. Symmetry breaking of normal modes dynamics and stretch-coil transitions are observed above the threshold of the buckling instability point. Furthermore, both temporal and spatial noise are amplified resulting from the interaction of thermal fluctuations and nonlinear filament dynamics. Specifically, the spatial noise is amplified with even normal modes being excited due to symmetry breaking, while the temporal noise is amplified with increasing time correlation length and variance.

Source: Soft Matter

DOI: 10.1039/c4sm02395a

Authors: Mingge Deng, Leopold Grinberg, Bruce Caswell, George Em Karniadakis

Institutions: Brown University, IBM (United States), IBM Research - Thomas J. Watson Research Center

Language: English

Topic: Rheology and Fluid Dynamics Studies

Subfield: Fluid Flow and Transfer Processes

Field: Chemical Engineering

Domain: Physical Sciences

Open Access status: green

Funders: U.S. Department of Energy, Worcester Polytechnic Institute, National Heart, Lung, and Blood Institute

Awards: G8116034371, G946812492