Keywords
simulation
multi-core processes
graphics coprocessors
high performance codes
lava flows
How to Cite
Abstract
this study discusses a depth-averaged model of viscous flow motion used in computer simulation of volcanic lava propagation. The mathematical properties of the model, its approximation methods, and numerical solution algorithms fine-tuned for modern hybrid computing clusters are presented. The mathematical model is a system of hyperbolic equations that simulate the laws of conservation of mass and momentum in the thin layer approximation. The terrain and rheological properties of the liquid and substance extrusion rate from the crater are specified as inhomogeneous members of the system. The proposed mathematical model offers high computational efficiency due to its two-dimensionality and the inclusion of free surface height as a variable in the equations. The paper also discusses parallel computer implementations of the model with OpenFOAM (MPI), OpenMP, and OpenACC. The codes run on CPU/GPU clusters with shared and distributed memory and Linux OS. The codes were verified using the analytical solution of the problem. We also profiled the codes for multi-core CPUs with shared memory.
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