Multiscale dissipative particle dynamics.

Gianni De Fabritiis; Peter V Coveney; Eirik G Flekkøy

doi:10.1098/rsta.2001.0956

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Multiscale dissipative particle dynamics.

Gianni De Fabritiis·Peter V Coveney·Eirik G Flekkøy

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Abstract

We present a simplified kinetic derivation of the multiscale Voronoi-based dissipative particle dynamics (DPD) method. The Voronoi tessellation is used to coarse-grain the molecular level of a fluid, resulting in mesoscopic equations of motion for local mass, momentum and energy. The dissipative particles follow the dynamics of extended objects subject to forces including pressure and stresses. The stresses and heat fluxes are computed through constitutive relations, which lead to fluctuating Navier-Stokes hydrodynamics for the solvent. The present formulation is based on the use of statistical mechanical distribution functions and the connection with the underlying molecular description of the fluid is maintained through the pair-distribution function and the intermolecular potential. The main features of this DPD method are the adaptivity of the dissipative particles to the important length-scales of the problem and the explicit role played by the molecular pair-distribution function.

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Biological Transport Colloids Computer Simulation Diffusion Kinetics Models, Biological Models, Chemical Models, Statistical Motion Particle Size Rheology Journal Article Research Support, Non-U.S. Gov't

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Gianni De Fabritiis, Peter V Coveney, Eirik G Flekkøy. 2002-03-15. Multiscale dissipative particle dynamics.. https://doi.org/10.1098/rsta.2001.0956

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