Three parallel algorithms for classical molecular dynamics are presented. The first assigns each processor a fixed subset of atoms; the second assigns each a fixed subset of inter-atomic forces to compute; the third assigns each a fixed spatial region. The algorithms are suitable for molecular dynamics models which can be difficult to parallelize efficiently—those with short-range forces where the neighbors of each atom change rapidly. They can be implemented on any distributed-memory parallel machine which allows for message-passing of data between independently executing processors. The algorithms are tested on a standard Lennard-Jones benchmark problem for system sizes ranging from 500 to 100,000,000 atoms on several parallel supercomputers--the nCUBE 2, Intel iPSC/860 and Paragon, and Cray T3D. Comparing the results to the fastest reported vectorized Cray Y-MP and C90 algorithm shows that the current generation of parallel machines is competitive with conventional vector supercomputers even for small problems. For large problems, the spatial algorithm achieves parallel efficiencies of 90% and a 1840-node Intel Paragon performs up to 165 faster than a single Cray C9O processor. Trade-offs between the three algorithms and guidelines for adapting them to more complex molecular dynamics simulations are also discussed.

Fast parallel algorithms for short-range molecular dynamics

介绍了Kirk—Othmer Encyclopedia of Chemical Technology（化工技术百科全书）（第五版）电子图书网络版数据库，并对该数据库使用方法和检索途径作出了说明，且结合实例简单地介绍了该数据库的检索方法。

Kirk-Othmer Encyclopedia of Chemical Technology数据库介绍及实例

An immersed boundary method with direct forcing for the simulation of particulate flows

The Maxwell-Stefan approach to mass transfer

Discrete particle simulation of particulate systems: A review of major applications and findings

Examples of complex flow characteristics observed in circulating fluidized beds and turbulent fluidized beds are presented. Different gas-particle modeling and simulation approaches that are being pursued to probe these flow characteristics are summarized. Major advances that are likely to emerge within the next decade are discussed.

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Reflections on Mathematical Models and Simulation of Gas-Particle Flows

The addition of small amounts (2-10 wt %) of SiO2 to A-Al2O3 increases the temperature of heat treatment necessary for transformation to R-Al2O3 by100 K. We have studied this system using high-temperature solution calorimetry in molten 2PbO‚B2O3 at 1043 K. Our results indicate that the spinel-type Al2O3-SiO2 solid solutions with 2-10 wt % SiO2 are always energetically metastable by 30-35 kJ‚mol -1 (on a4O 2 - per mole basis) with respect to R-Al2O3 and quartz. Calculation of the maximum configurational entropy of the solid solutions allowed determination of the likely most negative value of the Gibbs free energy of the materials. The solid solutions are somewhat entropy stabilized, but still thermodynamically metastable by >10 kJ‚mol -1 at 1400 K. Therefore, SiO2addition appears to provide mainly a kinetic hindrance to R-Al2O3 formation.

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Sankaran Sundaresan

Papers

Reflections on Mathematical Models and Simulation of Gas-Particle Flows

Metastability of Spinel-type Solid Solutions in the SiO2-Al2O3 System

Experimental and computational studies of dense granular flow: Transition from quasi-static to intermediate regime in a Couette shear device

Numerical studies of the effects of fines on fluidization

Sub-grid models for heat transfer in gas-particle flows with immersed horizontal cylinders