A Hard Constraint Algorithm to Model Particle Interactions in DNA-Laden Flows

Abstract

We present a new numerical method for particle interactions in polymer-fluid models of DNA-laden flows. The DNA is represented by a bead-rod polymer model and is fully-coupled to the fluid. The main objective in this work is to properly model polymer-polymer and polymer-surface interactions by enforcing the physical rod-rod and rod-surface non-crossing constraints. Our new method is based on a rigid constraint algorithm whereby rods elastically bounce off one another to prevent crossing, similar to our previous algorithm used to model polymer-surface interactions.

KEY WORDS:

• microfluidics
• fluid-polymer coupling
• viscoelasticity
• Navier-Stokes
• multiscale computational modeling

Notes

∗This work was performed under the auspices of the U.S. Department of Energy by the University of California, Lawrence Livermore National Laboratory under contract No. W-7405-Eng-48. The work of G.H. Miller at the University of California, Davis, was supported by LLNL IUT subcontract number B550201 and partially supported by DOE MICS contract number DE-FG02-03ER25579. The work of M.D. Bybee at the Lawrence Livermore National Laboratory was supported by the Department of Energy Computational Science Graduate Fellowship Program under grant number DE-FG02-97ER25308.