WG3: Review of meeting in Helsinki, Finland on 16th May 2024

Brief Summary

File format

HDF5 offers a flexible file format for storing complex data and metadata. Metadata allows files to be self-describing and is suitable for storing details regarding the simulation, allowing data to be stored in a common format for all DEM codes.

Well supported across various computing libraries.

Two possible options:

1. Define a file structure that allows all aspects of a DEM simulation to be recorded

   1. Simulation metadata (materials, interactions, domain, etc)

   2. Particle information

   3. contact information

2. Use VTKHDF which offers a predefined HDF5 based format for data visualisation but fixed layout

   1. may not be possible to store all data required for interoperability for storing a complete simulation (metadata not officially supported)

   2. Easy of visualisation (read directly in paraview)

   3. Temporal support for large datasets not mature enough (single file only and not suitable for very large multi-timestep simulations)

Both options need development to capture a DEM

Required Data Structure

VELaSSCo format serves as example format (Ascii based) on how to structure.

It was decided that we need to display a hierarchy of data with normalized names in order to export / import simulations from one code to another.

Some data will be flagged as “mandatory” – needed for saving the simulation – while other will be flagged as “optional” – this is used for post-processing only.

A sketch of this framework (as discussed during the meeting) is shown below:

Open