4 research outputs found
Scalable hierarchical parallel algorithm for the solution of super large-scale sparse linear equations
The parallel linear equations solver capable of effectively using 1000+
processors becomes the bottleneck of large-scale implicit engineering
simulations. In this paper, we present a new hierarchical parallel
master-slave-structural iterative algorithm for the solution of super
large-scale sparse linear equations in distributed memory computer cluster.
Through alternatively performing global equilibrium computation and local
relaxation, our proposed algorithm will reach the specific accuracy requirement
in a few of iterative steps. Moreover, each set/slave-processor majorly
communicate with its nearest neighbors, and the transferring data between
sets/slave-processors and master is always far below the set-neighbor
communication. The corresponding algorithm for implicit finite element analysis
has been implemented based on MPI library, and a super large 2-dimension square
system of triangle-lattice truss structure under random static loads is
simulated with over one billion degrees of freedom and up to 2001 processors on
"Exploration 100" cluster in Tsinghua University. The numerical experiments
demonstrate that this algorithm has excellent parallel efficiency and high
scalability, and it may have broad application in other implicit simulations.Comment: 23 page, 9 figures 1 tabl
Broadband transmission losses and time dispersion maps from time-domain numerical simulations in ocean acoustics
In this letter, a procedure for the calculation of transmission loss maps from numerical simulations in the time domain is presented. It can be generalized to arbitrary time sequences and to elastic media and provides an insight into how energy spreads into a complex configuration. In addition, time dispersion maps can be generated. These maps provide additional information on how energy is distributed over time. Transmission loss and time dispersion maps are generated at a negligible additional computational cost. To illustrate the type of transmission loss maps that can be produced by the time-domain method, the problem of the classical two-dimensional upslope wedge with a fluid bottom is addressed. The results obtained are compared to those obtained previously based on a parabolic equation. Then, for the same configuration, maps for an elastic bottom and maps for non-monochromatic signals are computed