Article
Version 1
Preserved in Portico This version is not peer-reviewed
Synchronized Molecular-Dynamics Simulation of the Thermal Lubrication of an Entangled Polymeric Liquid
Version 1
: Received: 7 November 2018 / Approved: 8 November 2018 / Online: 8 November 2018 (15:00:16 CET)
A peer-reviewed article of this Preprint also exists.
Yasuda, S. Synchronized Molecular-Dynamics Simulation of the Thermal Lubrication of an Entangled Polymeric Liquid. Polymers 2019, 11, 131. Yasuda, S. Synchronized Molecular-Dynamics Simulation of the Thermal Lubrication of an Entangled Polymeric Liquid. Polymers 2019, 11, 131.
Abstract
The thermal lubrication of an entangled polymeric liquid in wall-driven shear flows between parallel plates is investigated by using a multiscale hybrid method coupling molecular dynamics and the hydrodynamics (i.e., the synchronized molecular dynamics method).
The temperature of the polymeric liquid rapidly increases due to viscous heating once the drive force exceeds a certain threshold value.
The rheological properties of the polymeric liquid drastically change at around the critical drive force.
In the weak viscous-heating regime, the conformation of polymer chains is dominated by the local shear flow so that the anisotropy of the bond orientation tensor grows as the drive force increases.
However, in the large viscous-heating regime, the conformation dynamics is dominated by the thermal agitation of polymer chains so that the bond orientation tensor recovers more uniform and random structures as the drive force increases, even though the local shear flows are further enhanced.
Remarkably, these counter-intuitive transitional behaviors give an interesting re-entrant transition in the stress--optical relation, where a linear formalism in the stress--optical relation approximately holds even though each of the macroscopic quantities behaves nonlinearly.
The robustness of the linear stress--optical relation is also confirmed in the spatiotemporal evolution at the hydrodynamic level.
Keywords
multi-scale modeling; lubrication; viscous heating; entangled polymeric liquid
Subject
Physical Sciences, Condensed Matter Physics
Copyright: This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Comments (0)
We encourage comments and feedback from a broad range of readers. See criteria for comments and our Diversity statement.
Leave a public commentSend a private comment to the author(s)
* All users must log in before leaving a comment