Tags

Type your tag names separated by a space and hit enter

Hydrodynamically Coupled Brownian Dynamics: A coarse-grain particle-based Brownian dynamics technique with hydrodynamic interactions for modeling self-developing flow of polymer solutions.
J Chem Phys 2018; 148(3):034902JC

Abstract

We present a novel coarse-grain particle-based simulation technique for modeling self-developing flow of dilute and semi-dilute polymer solutions. The central idea in this paper is the two-way coupling between a mesoscopic polymer model and a phenomenological fluid model. As our polymer model, we choose Responsive Particle Dynamics (RaPiD), a Brownian dynamics method, which formulates the so-called "conservative" and "transient" pair-potentials through which the polymers interact besides experiencing random forces in accordance with the fluctuation dissipation theorem. In addition to these interactions, our polymer blobs are also influenced by the background solvent velocity field, which we calculate by solving the Navier-Stokes equation discretized on a moving grid of fluid blobs using the Smoothed Particle Hydrodynamics (SPH) technique. While the polymers experience this frictional force opposing their motion relative to the background flow field, our fluid blobs also in turn are influenced by the motion of the polymers through an interaction term. This makes our technique a two-way coupling algorithm. We have constructed this interaction term in such a way that momentum is conserved locally, thereby preserving long range hydrodynamics. Furthermore, we have derived pairwise fluctuation terms for the velocities of the fluid blobs using the Fokker-Planck equation, which have been alternatively derived using the General Equation for the Non-Equilibrium Reversible-Irreversible Coupling (GENERIC) approach in Smoothed Dissipative Particle Dynamics (SDPD) literature. These velocity fluctuations for the fluid may be incorporated into the velocity updates for our fluid blobs to obtain a thermodynamically consistent distribution of velocities. In cases where these fluctuations are insignificant, however, these additional terms may well be dropped out as they are in a standard SPH simulation. We have applied our technique to study the rheology of two different concentrations of our model linear polymer solutions. The results show that the polymers and the fluid are coupled very well with each other, showing no lag between their velocities. Furthermore, our results show non-Newtonian shear thinning and the characteristic flattening of the Poiseuille flow profile typically observed for polymer solutions.

Authors+Show Affiliations

Computational Chemical Physics, Faculty of Science and Technology, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands.Physical Chemistry and Soft Matter, Wageningen University, Building 124, Stippeneng 4, 6708 WE, Wageningen, The Netherlands.Computational Chemical Physics, Faculty of Science and Technology, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands.

Pub Type(s)

Journal Article

Language

eng

PubMed ID

29352779

Citation

Ahuja, V R., et al. "Hydrodynamically Coupled Brownian Dynamics: a Coarse-grain Particle-based Brownian Dynamics Technique With Hydrodynamic Interactions for Modeling Self-developing Flow of Polymer Solutions." The Journal of Chemical Physics, vol. 148, no. 3, 2018, p. 034902.
Ahuja VR, van der Gucht J, Briels WJ. Hydrodynamically Coupled Brownian Dynamics: A coarse-grain particle-based Brownian dynamics technique with hydrodynamic interactions for modeling self-developing flow of polymer solutions. J Chem Phys. 2018;148(3):034902.
Ahuja, V. R., van der Gucht, J., & Briels, W. J. (2018). Hydrodynamically Coupled Brownian Dynamics: A coarse-grain particle-based Brownian dynamics technique with hydrodynamic interactions for modeling self-developing flow of polymer solutions. The Journal of Chemical Physics, 148(3), p. 034902. doi:10.1063/1.5006627.
Ahuja VR, van der Gucht J, Briels WJ. Hydrodynamically Coupled Brownian Dynamics: a Coarse-grain Particle-based Brownian Dynamics Technique With Hydrodynamic Interactions for Modeling Self-developing Flow of Polymer Solutions. J Chem Phys. 2018 Jan 21;148(3):034902. PubMed PMID: 29352779.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Hydrodynamically Coupled Brownian Dynamics: A coarse-grain particle-based Brownian dynamics technique with hydrodynamic interactions for modeling self-developing flow of polymer solutions. AU - Ahuja,V R, AU - van der Gucht,J, AU - Briels,W J, PY - 2018/1/22/entrez PY - 2018/1/22/pubmed PY - 2018/1/22/medline SP - 034902 EP - 034902 JF - The Journal of chemical physics JO - J Chem Phys VL - 148 IS - 3 N2 - We present a novel coarse-grain particle-based simulation technique for modeling self-developing flow of dilute and semi-dilute polymer solutions. The central idea in this paper is the two-way coupling between a mesoscopic polymer model and a phenomenological fluid model. As our polymer model, we choose Responsive Particle Dynamics (RaPiD), a Brownian dynamics method, which formulates the so-called "conservative" and "transient" pair-potentials through which the polymers interact besides experiencing random forces in accordance with the fluctuation dissipation theorem. In addition to these interactions, our polymer blobs are also influenced by the background solvent velocity field, which we calculate by solving the Navier-Stokes equation discretized on a moving grid of fluid blobs using the Smoothed Particle Hydrodynamics (SPH) technique. While the polymers experience this frictional force opposing their motion relative to the background flow field, our fluid blobs also in turn are influenced by the motion of the polymers through an interaction term. This makes our technique a two-way coupling algorithm. We have constructed this interaction term in such a way that momentum is conserved locally, thereby preserving long range hydrodynamics. Furthermore, we have derived pairwise fluctuation terms for the velocities of the fluid blobs using the Fokker-Planck equation, which have been alternatively derived using the General Equation for the Non-Equilibrium Reversible-Irreversible Coupling (GENERIC) approach in Smoothed Dissipative Particle Dynamics (SDPD) literature. These velocity fluctuations for the fluid may be incorporated into the velocity updates for our fluid blobs to obtain a thermodynamically consistent distribution of velocities. In cases where these fluctuations are insignificant, however, these additional terms may well be dropped out as they are in a standard SPH simulation. We have applied our technique to study the rheology of two different concentrations of our model linear polymer solutions. The results show that the polymers and the fluid are coupled very well with each other, showing no lag between their velocities. Furthermore, our results show non-Newtonian shear thinning and the characteristic flattening of the Poiseuille flow profile typically observed for polymer solutions. SN - 1089-7690 UR - https://www.unboundmedicine.com/medline/citation/29352779/Hydrodynamically_Coupled_Brownian_Dynamics:_A_coarse_grain_particle_based_Brownian_dynamics_technique_with_hydrodynamic_interactions_for_modeling_self_developing_flow_of_polymer_solutions_ L2 - https://dx.doi.org/10.1063/1.5006627 DB - PRIME DP - Unbound Medicine ER -