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Published on: September 26, 2016
Schmidt number effects in dissipative particle dynamics simulation of polymers
Vasileios Symeonidis1, George Em Karniadakis, Bruce Caswell
1Division of Applied Mathematics, Brown University, Providence, Rhode Island 02912, USA. sjoh0341@dam.brown.edu
The Journal of Chemical Physics
|November 23, 2006
Summary
The Schmidt number (S(c)) of the solvent significantly influences polymer behavior in simulations. This study reveals how S(c) affects polymer chain extension and flow dynamics in microchannels.
Area of Science:
- Computational physics
- Polymer science
- Fluid dynamics
Background:
- Understanding polymer behavior in dilute systems is crucial for various applications.
- Non-equilibrium polymer dynamics are complex and influenced by solvent properties.
- Dissipative Particle Dynamics (DPD) is a suitable method for simulating such systems.
Purpose of the Study:
- To investigate the influence of the solvent's Schmidt number (S(c)) on polymeric quantities in non-equilibrium simulations.
- To analyze polymer chain extension under shear flow as a function of S(c).
- To study non-uniform concentration profiles and flow behavior in microchannels.
Main Methods:
- Dissipative Particle Dynamics (DPD) simulations were employed.
- Two thermostats (velocity-Verlet and Lowe's scheme) were utilized.
- Simulations included steady shear flow and Poiseuille flow in microchannels.
Main Results:
- The Schmidt number (S(c)) strongly affects non-equilibrium polymeric quantities.
- Fractional extension of wormlike chains under shear depends on S(c).
- Non-uniform concentration profiles in microchannels were computed and shown to depend on S(c).
- Bounce-forward wall boundary conditions impact depletion layer thickness.
- Wall viscosities differ from bulk values, and slip flow models are inadequate.
Conclusions:
- Solvent properties, specifically the Schmidt number, play a critical role in polymer dynamics under flow.
- DPD simulations provide insights into microchannel flow and polymer behavior.
- Current slip flow models may not accurately describe these complex flow conditions.
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