Transport coefficients of soft sphere fluids
1Division of Chemistry, School of Biomedical and Molecular Sciences, University of Surrey, Guildford, UK GU2 7XH. d.heyes@surrey.ac.uk
Physical Chemistry Chemical Physics : PCCP
|October 2, 2009
Summary
This study reveals how fluid transport properties, like self-diffusion and viscosity, depend on interaction softness. Transport coefficients correlate with entropy, with best results for diffusion.
Area of Science:
- Thermodynamics
- Fluid Dynamics
- Computational Physics
Background:
- Understanding fluid transport properties is crucial in various scientific fields.
- The influence of interaction softness on these properties requires detailed investigation.
Purpose of the Study:
- To explore the effects of interaction softness on fluid transport properties.
- To test semi-empirical formulae against simulation data.
- To investigate the relationship between transport coefficients and entropy.
Main Methods:
- Molecular dynamics simulations were employed.
- Calculated self-diffusion coefficient (D), shear viscosity (eta(s)), bulk viscosity (eta(b)), and thermal conductivity (lambda).
- Tested semi-empirical formulae and cell models.
Main Results:
- Transport coefficients showed proportionality to the exponential of the two-body component of entropy.
- Agreement quality varied, being best for D and worst for lambda.
- A cell model based on mean square force was unsuccessful for diffusion coefficient correlation.
Conclusions:
- Interaction softness significantly impacts fluid transport properties.
- The entropy-based correlation provides insights but has limitations.
- Further refinement of models is needed for accurate prediction across wide parameter ranges.
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