Dynamics of an electrostatically charged elastic rod in fluid

作者:Lim Sookkyung*; Kim Yongsam; Swigon David
来源:Proceedings of the Royal Society A-Mathematical Physical and Engineering Sciences, 2011, 467(2126): 569-590.
DOI:10.1098/rspa.2010.0174

摘要

We investigate the effects of electrostatic and steric repulsion on the dynamics of a pre-twisted charged elastic rod immersed in a viscous incompressible fluid. Equations of motion of the rod include the fluid-structure interaction, rod elasticity and a combination of two interactions that prevent self-contact, namely the electrostatic interaction and hard-core repulsion. The governing equations are solved using the generalized immersed-boundary method. We find that after perturbation, a pre-twisted minicircle collapses into a compact supercoiled configuration. The collapse proceeds along a complex trajectory that may pass near several unstable equilibrium configurations, before it settles in a locally stable equilibrium. The dwell time near an unstable equilibrium can be up to several microseconds. Both the final configuration and the transition path are sensitive to the initial excess link, ionic strength of the solvent and the initial perturbation.

  • 出版日期2011-2-8