Invariance of experimental observables with respect to coarse-graining in standard and many-body dissipative particle dynamics

Abstract

Dissipative particle dynamics (DPD) is a well-established mesoscale simulation method. However, there have been long-standing ambiguities regarding the dependence of its (purely repulsive) force field parameter on temperature as well as the variation of the resulting experimental observables, such as diffusivity or surface tension, with coarse-graining (CG) degree. Here, we revisit the role of the CG degree and rederive the temperature dependence in standard DPD simulations. Consequently, we derive a scaling of the input variables that renders the system properties invariant with respect to CG degree, and illustrate the versatility of the method by computing the surface tensions of binary solvent mixtures. We then extend this procedure to many-body dissipative particle dynamics (MDPD) and, by computing surface tensions of the same mixtures at a range of CG degrees, demonstrate that this newer method, which has not been widely applied so far, is also capable of simulating complex fluids of practical interest.

arXiv comment12 pages, 7 figures, published version

References in corpus (6)

• Perspective: Dissipative Particle Dynamics
• Vapour-liquid coexistence in many-body dissipative particle dynamics
• Dissipative particle dynamics for interacting systems
• Dissipative particle dynamics: systematic parametrization using water-octanol partition coefficients
• No-go theorem in many body dissipative particle dynamics
• Liquid phase parametrisation and solidification in many-body dissipative particle dynamics

Cited by in corpus (1)

• Definitions of local density in density-dependent potentials for mixtures