A smoothed dissipative particle dynamics methodology for wall-bounded domains

Jun Yang

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arXiv · 1708.06993

A smoothed dissipative particle dynamics methodology for wall-bounded domains

Jun Yang

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Abstract

This work presents the mathematical and computational aspects of a smooth dissipative particle dynamics with dynamic virtual particle allocation method (SDPD-DV) for modeling and simulation of mesoscopic fluids in wall-bounded domains. The SDPD-DV method is realized with fluid particles, boundary particles and dynamically allocated virtual particles near solid boundaries. The physical domain in SDPD-DV contains external and internal solid boundaries, periodic inlets and outlets, and the fluid region. The solid boundaries of the domain are represented with boundary particles which have an assigned position, wall velocity, and temperature upon initialization. The fluid domain is discretized with fluid particles placed in a global index. The algorithm for nearest neighbor particle search is based on a combination of the linked-cell and Verlet-list approaches and utilizes large rectangular cells for computational efficiency. The density model of a fluid particle in the proximity of a solid boundary includes the contribution from the virtual particles in its truncated support domain. The thermodynamic properties of a virtual particle are identical to those of the corresponding fluid particle. Additional verification involves SDPD-DV simulations of transient, planar, Couette liquid water flow. The top plate is moving at and separated by 10-3 m from the bottom stationary plate. The numerical results are in very good agreement with the analytical solutions. Additional SDPD-DV verification is accomplished with the simulation of a body-force driven, low-Reynolds number flow of water over a cylinder of radius . The SDPD-DV field velocity and pressure are compared with those obtained by FLUENT.

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Jun Yang. 2017-08-01. A smoothed dissipative particle dynamics methodology for wall-bounded domains. https://arxiv.org/abs/1708.06993

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