Parallel simulation of shear flow of polymers between structured walls by molecular dynamics simulation on PVM

Abstract

A parallel algorithm has been developed for the simulation of Couette shear flow between structured walls. The algorithm is designed to simulate the shear flow of atomic and molecular fluids. The parallel link-cells model is used for parallelization with some modifications for accomodating the nonperiodic boundaries in the wall direction. Some techniques are also introduced for handling the non-homogeneous nature of the flow in the proximity of the physical walls in order to achieve a balanced workload between processors. PVM (Parallel Virtual Machine) is employed as the message passing paradigm for communication between the processors. The algorithm has been tested for a number of benchmarks with different sizes for simulating the shear flow of n-hexadecane. The maximum number of processors used was 28 DEC Alpha 500/256 workstations which were connected by a 100 Mbits/s Ethernet. A maximum speedup of 11 was obtained with 28 processors. The efficiency ranged from 92% to 40% depending on the number of processors and the system size.