Program of 2015 Dpd Workshop Day One

Smoothed Particle Hydrodynamics (SPH) is a Lagrangian method based on a meshless discretization of partial differential equations. I will present SPH discretization of the stochastic and deterministic Navier-Stokes and Advection-Diffusion-Reaction equations, implementation of various boundary conditions, and time integration of the SPH equations, and discuss applications of the SPH method for modeling multiphase flows and reactive transport in domains with complex geometries. [22] Zhong-Yuan Lu, Institute of Theoretical Chemistry, Jilin University, China. Title: Multiscale Simulation Study of Polymer Systems Based on Dissipative Particle Dynamics. Abstract: Due to large molecular size and slow relaxation of polymer chains, a great amount of issues related to long-distance chain displacement, such as phase separation and self-assembly, can not be tackled easily with conventional molecular dynamic simulations. We need to use generic polymer models based on dissipative particle dynamics (DPD) to solve problems commonly encountered in polymer phase separation and self-assembly. A soft patchy particle model originated from DPD, which is suitable to describe “soft” particle formed by star-like polymers and dendrimers, has been proposed to study their self-assembly structures. A stochastic reaction model in DPD simulations has been used to cope with the problems related to the coupling between polymerization and chain diffusion. We have also developed a GPU-accellerated molecular simulation toolkit for use in coarse-grained simulations of polymer systems with several unique simulation tools implemented. [23] Tutorial Session Instructor 1: Yu-Hang Tang, Division of Applied Mathematics, Brown University, USA. Title: Practicing Dissipative Particle Dynamics. Content: This tutorial will be focused on using the LAMMPS software to conduct and post-process DPD simulations. Techniques for constructing initial configuration of particle systems will be demonstrated, followed by basic scripting for enabling various integration schemes and custom functionalities. Compiling and configuring LAMMPS for parallel execution will also be covered. No previous experience with LAMMPS is required. Instructor 2: Changho Kim, Division of Applied Mathematics, Brown University, USA. Title: Calculating material properties from LAMMPS. Content: For various ways of calculating transport coefficients, including the non-equilibrium simulation approach and the Green-Kubo method, the actual implementations on LAMMPS are demonstrated. The underlying principles from statistical mechanics are also reviewed and possible computational issues are discussed. In addition, it is discussed how the sampling uncertainties and the finite-systemsize effects are quantified in particle dynamics simulations.