Paper Number
PO43 

Session
Poster Session

Title
Diffusion tensor calculation for coarse-grained polymer models with fluctuating internal friction and hydrodynamic interactions

Presentation Date and Time
October 12, 2022 (Wednesday) 6:30

Track / Room
Poster Session / Riverwalk A

Authors (Click on name to view author profile)

  1. Kailasham, R. (Carnegie Mellon University, Department of Chemical Engineering)
  2. Chakrabarti, Rajarshi (Indian Institute of Technology Bombay, Department of Chemistry)
  3. Prakash, J. Ravi (Monash University, Chemical and Biological Engineering)

Author and Affiliation Lines (in printed abstract book)
R. Kailasham1, Rajarshi Chakrabarti2 and J. Ravi Prakash3
1Department of Chemical Engineering, Carnegie Mellon University, Pittsburgh, PA 15213; 2Department of Chemistry, Indian Institute of Technology Bombay, Mumbai, Maharashtra 400076, India; 3Chemical and Biological Engineering, Monash University, Melbourne, Victoria 3800, Australia

Speaker / Presenter 
Kailasham, R.

Keywords
theoretical methods; computational methods; polymer solutions

Text of Abstract
An exact solution of coarse-grained polymer models with fluctuating internal friction and hydrodynamic interactions has not been proposed so far due to a one-to-all coupling between the connector vector velocities that precludes the formulation of the governing stochastic differential equations. A methodology for the removal of this coupling is presented [1], and the governing stochastic differential equations, obtained by attaching a kinetic interpretation to the Fokker-Planck equation for the system, are integrated numerically using Brownian dynamics simulations. The proposed computational route eliminates the calculation of the divergence of the diffusion tensor which appears in models with internal friction, and is about an order of magnitude faster than the recursion-based algorithm for the decoupling of connector-vector velocities previously developed [J. Rheol. 65, 903 (2021)] for the solution of freely draining models with internal friction. The effects of the interplay of various combinations of finite extensibility, internal friction and hydrodynamic interactions on the steady-shear-viscosity is examined. While finite extensibility leads solely to shear-thinning, both internal friction and hydrodynamic interactions result in shear-thinning followed by shear-thickening. The shear-thickening induced by internal friction effects are more pronounced than that due to hydrodynamic interactions.

References
[1] R. Kailasham, R. Chakrabarti, and J. R. Prakash, https://doi.org/10.48550/arXiv.2204.10656