Influence of the conservative force on transport coefficients in the DPD method

Abstract

The transport coefficients of a dissipative particle dynamics system are investigated numerically taking into account the conservative force. The influence of the conservative force parameter on kinetic and dissipative viscosity is considered and compared with theoretical predictions. The analytical solution of the potential term that arises from the conservative force is generally very complicated; therefore, this term has been ignored in most previous work and deemed negligible. In the present work, an expression for the effect of the conservative force on potential viscosity is semi-empirically obtained revealing the dependence of the latter on various parameters such as conservative force strength, density number and temperature. This relation offers a proper approximation of conservative force impact on potential viscosity.

Keywords:

• Dissipative particle dynamics
• transport coefficient
• viscosity
• self-diffusion coefficient
• conservative force

Acknowledgements

We thank H. Karimpour for helpful discussions. We also gratefully acknowledge the Sheikh Bahaei National High Performance Computing Center (SBNHPCC) for providing computing facilities.