Earlier in November 2024, below food-for-thought information was shared with almost all of the WG1 members to help achieve our goal for 2025.
Benchmarking
Problem description
We will use a tumbling drum for our benchmark case as there should be experimental data from a number of groups along with it being simple enough that most codes can simulate.
For the DEM Model we will use Hertz Mindlin as done in this paper with appropriate YM and time-step values, https://www.sciencedirect.com/science/article/pii/S0010465523004113
We will have a case with moderate particle numbers that we will use to calibrate against experiment.
We will do an additional case with a larger number of particles in a range of millions to benchmark performance
We will do a shape case using cubes as they are simple enough that most codes will have some representation for it. We aim to calibrate against experiment and will do a larger case as a performance study as in the case with spheres.
What to measure?
The key metrics will be
mixing index (same material, two colors) Hongyang Cheng
power (summation of the dashpot and friction dissipation energies) torque arm Bruno Chareyre do you have a script ? Code
Torque Code
profile outline .Code
To generate the above metrics, we aim to get post-process analysis scripts that people already have to compare between codes and to experiment.
What we require
Experiment and simulation data along with the configuration usedBase Case Anthony Thornton Drum.
The code that you want to use and/or if you are willing to run cases.
If you can help with scripts for processing the results or have suggestions.
What we need to deliver
Officially we need to have at-least two open source codes with the implementations
Currently we have commitments for Yade and Mercury.
Beyond that, any code that you want can be used as we aim to compare in a code agnostic manner.
What we want to achieve in 2025
Overview and comparison of different time-efficient computational strategies and methods (HPC vs Upscaling vs Surrogates)
Start with DEM glass beads
Comparison with real world ground truth
Hackathon plan
Presenting the WG1 Update
https://docs.google.com/presentation/d/1A-1bW1kANEfAay8pCeZmq3zH3Qhoo1HOjlxsja4-f0U/edit?usp=sharing
Identify available rotating drum datasets
Experimental
Ben Jenkins Is the data open-access?
DEM
Datasets
There is data corresponding to linear spring model. Correct Timo Plath? If yes, how can we download it?
- Timo Plath is on it
Codebases to generate datasets from scratch
Open-source
(semi/fully) Closed-source
https://gitlab.com/gdigitaltwins
nicolin did the implementation in Blaze and provides Blaze binary
Ben Jenkins LIGGGHTS
Rocky
Execution
Split into two groups HPC and Alternative Methods (AI/ML, Surrogate models)
G1 - HPC by nicolin
Assign tasks to complete the benchmark case of the rotating drum
G2 - Alternative methods by Deepak Tunuguntla Hongyang Cheng
Talk by Timo Plath on Reduced Order DPM
Setup a central github repo for all the relevant ML-based algorithms for granular materials
To be cont.
Additional references
Different calibration techniques
Yannick Descantes has a test case that we will use to check numerical stability in heap formation.
Timo Plath has a script in MercuryDPM for Rotating drum and Surrogate model calibration
Summary and action points
For this high performance comparison study, we will start with DEM using Silbert's glass spheres validated contact parameters for Linear Spring and Hertz-Mindlin
See Silbert’s paper and add a table of contact parameters here
Mono- and bi-disperse
For speed test
Turn on and off energy computations
Turn on and off data saving
How long do you want the run the simulation? x seconds
How often do we want to save data? y times
For surrogates
Generate our own datasets
Action points
- nicolin Deepak Tunuguntla to provide input data
Drum size, speed,
DEM parameters from Silbert’s paper
How do you generate the number of particles?, particle-wall friction,
- Deepak Tunuguntla Schedule a meeting
- Deepak Tunuguntla Create a Q&A / Discussion page for WG1
- Who will generate datasets tentative
Open-source
Yade - Bruno Chareyre Radan Ivanov Roxana Saghafian Larijani
MercuryDPM - Timo Plath Jan-Willem Bisschop Thomas Weinhart Anthony Thornton Deepak Tunuguntla
Liggghts-public - Hamed, Ben Jenkins (to confirm)
Closed-source
Blaze - Rafal Kobylka nicolin
Musen - Mikhail ()
- Hardware
CPU Parallellisation Bruno Chareyre Anthony Thornton Burek
OpenMP
1 core, 10 core, 20 core
MPI
10 core, 100 core, 1000o cores
GPU parallelisation nicolin Yannick Descantes John P. Morrissey