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

Smoothed particle hydrodynamics (SPH) is a meshfree particle method based on Lagrangian formulation, and has been widely applied to different areas in engineering and science. This paper presents an overview on the SPH method and its recent developments, including (1) the need for meshfree particle methods, and advantages of SPH, (2) approximation schemes of the conventional SPH method and numerical techniques for deriving SPH formulations for partial differential equations such as the Navier-Stokes (N-S) equations, (3) the role of the smoothing kernel functions and a general approach to construct smoothing kernel functions, (4) kernel and particle consistency for the SPH method, and approaches for restoring particle consistency, (5) several important numerical aspects, and (6) some recent applications of SPH. The paper ends with some concluding remarks.

Smoothed Particle Hydrodynamics (SPH): an Overview and Recent Developments

Lunar sourcebook. A user's guide to the moon

Impact behaviour of fibre-reinforced composites Recent developments in impact damage assessment of fibre composites Modelling impact of composite structures using small specimens Impact damage - tolerant composite structural design Damage resistance and tolerance of thick laminated woven roving GFRP plates subjected to low-velocity impact Elastic impact stress analysis of composite plates and cylinders Impact behaviour and analysis of CFRP laminated plates Perforation of FRP laminates and sandwich panels subjected to missile impact High velocity impact damage to polymer matrix composites

Impact behaviour of fibre-reinforced composite materials and structures

Innovative honeycomb-based structures have been paid substantial attention in recent years due to their superb mechanical performances and specific functions. The presented study made acomprehensive overview on the development of the innovative honeycomb-based structures in the past two decades, including filled-type, embedded, tandem, hierarchical, auxetics with Negative Poisson's Ratio (NPR), etc. Mechanical performances of these structures were commented with advantages and disadvantages, related on their geometric configurations, mechanical performance and dynamic response, respectively. The challenges as well as future directions were also analyzed. The achievements provide significant guidelines in designing of new generation light-weight honeycomb-based structures.

Recent advances in novel metallic honeycomb structure

Hypervelocity impact on carbon fibre reinforced plastic / aluminium honeycomb: Comparison with whipple bumper shields

Materials blasted into space from the surface of early Earth may preserve a unique record of our planet's early surface environment. Armstrong et al. (2002) pointed out that such materials...

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Emma A. Taylor

Papers

Hypervelocity impact on carbon fibre reinforced plastic / aluminium honeycomb: Comparison with whipple bumper shields

On the survivability and detectability of terrestrial meteorites on the moon

Normal and oblique hypervelocity impacts on carbon fibre/peek composites

Hypervelocity Impact On Spacecraft Honeycomb: Hydrocode Simulation And Damage Laws

Hydrocode modelling of hypervelocity impact on brittle materials : Depth of penetration and conchoidal diameter