Introduction

topIIvol meshing tool provides sequential and parallel tools for creating volumetric tetrahedral meshes from a given terrain topology via digital elevation model (DEM point-cloud *.xyz). Via this plugin one could produce distributed meshes suitable for domain-decomposition based solvers or simply non distributed meshes (single mesh) suitable for a sequential/parallel solver.

Running topIIvol Plug-in

topIIVolMesh plug-in can be invoked via SMESH Plugin item in Mesh menu bar

_images/callTopIIVolMesh.png

topIIVolMesh Options

Users have option of performing meshing via:

  • Sequential mode: mesh computation in sequential and outputs a single mesh.

  • Parallel mode: mesh computation in parallel and outputs a single mesh.

  • Parallel distributed mode: mesh computation in parallel and outputs partitioned meshes.

Sequential mode

By default sequential meshing mode is activated. topIIvol_Mesher sequential tool is called for creating volumetric tetrahedral mesh for the given DEM point-cloud. The volumetric mesh can be displayed in SALOME by ticking the “Display mesh” check-box.

The list of input parameters are:

  • DEM input file: input point cloud file in .xyz format;

  • Number of X points present in the input point cloud;

  • Number of Y points present in the input point cloud;

  • Number of Z points intended in the Z direction;

  • Depth of the mesh needed;

  • temporary directory for calculation.

Parallel mode

For larger meshes the parallel meshing mode can be activated via the check-box Parallel. Additionally, this requires the user to provide the number of processors to be used for parallel meshing. Then, topIIvol_ParMesher parallel computing tool is called for creating volumetric tetrahedral mesh for the given DEM point-cloud. The volumetric mesh can be displayed in SALOME by ticking the “Display mesh” check-box.

The list of input parameters are:

  • DEM input file: input point cloud file in .xyz format;

  • Number of X points present in the input point cloud;

  • Number of Y points present in the input point cloud;

  • Number of Z points intended in the Z direction;

  • Depth of the mesh needed;

  • Number of MPI ranks

  • temporary directory for calculation.

Parallel distributed mode

For larger meshes suitable for distributed-memory solvers (domain-decomposition) the distributed parallel meshing mode can be activated via the check-box Parallel distributed. This requires the user to provide the number of processors to be used for parallel meshing and how to partition the mesh in each direction (X, Y, Z). Then, topIIvol_DistMesher computing tool is called for creating embarrassingly parallel distributed meshes for the given DEM point-cloud. These volumetric mesh partitions can be displayed in SALOME by ticking the “Display mesh” check-box.

The list of input parameters are:

  • DEM input file: input point cloud file in .xyz format;

  • Number of X points present in the input point cloud;

  • Number of Y points present in the input point cloud;

  • Number of Z points intended in the Z direction;

  • Depth of the mesh needed;

  • Number of partitions in X direction;

  • Number of partitions in Y direction;

  • Number of partitions in Z direction;

  • Number of MPI ranks

  • temporary directory for calculation.