On finite size effects, ensemble choice and force influence in dissipative particle dynamics simulations

TL;DR

This paper examines finite size effects, ensemble choices, and force contributions in dissipative particle dynamics simulations, providing insights and practical tips for accurate property predictions in numerical modeling.

Contribution

It offers a detailed analysis of finite size effects, emphasizes the importance of ensemble selection, and explores force contributions in DPD, with practical simulation tips.

Findings

Finite size effects are minimal for stress anisotropy, interfacial tension, and viscosity.

Ensemble choice significantly impacts property calculations, especially in small systems.

Force contributions vary, with practical recommendations for high-performance DPD simulations.

Abstract

The influence of finite size effects, choice of statistical ensemble and contribution of the forces in numerical simulations using the dissipative particle dynamics (DPD) model are revisited here. Finite size effects in stress anisotropy, interfacial tension and dynamic viscosity are computed and found to be minimal with respect to other models. Additionally, the choice of ensemble is found to be of fundamental importance for the accurate calculation of properties such as the solvation pressure, especially for relatively small systems. Lastly, the contribution of the random, dissipative and conservative forces that make up the DPD model in the prediction of properties of simple liquids such as the pressure is studied as well. Some tricks of the trade are provided, which may be useful for those carrying out high-performance numerical simulations using the DPD model.