Particle Micromechanics
Contact interactions between particles and walls play a crucial role in many particle technology processes, including fluidized beds, filtration, additive manufacturing, milling, and pneumatic or hydraulic conveying. During these interactions, micromechanical phenomena such as adhesion, deformation, friction, attrition, and breakage govern the overall behavior of particulate systems.
The Particle Micromechanics group investigates the micromechanical behavior of individual particles and agglomerates through advanced experiments and modeling to link microscopic contact phenomena with macroscopic process performance.
Team
Contact: M.Sc. Fabian Krull
Research Areas
At the Laboratory for Particle Micromechanics, we apply compression tests, nanoindentation, tribological measurements, and collision experiments under controlled environmental and temperature conditions. These data form the basis for physically based contact models, implemented in the Discrete Element Method (DEM) and validated through numerical simulations.
Custom-built setups enable the study of dynamic particle-particle and particle-wall collisions in gaseous and liquid media (Figure). A free-fall apparatus allows 3D high-speed visualization of impacts, while a pneumatic system examines liquid bridge formation and adhesion effects. These techniques are also used to characterize the mechanical properties of biological cell aggregates (spheroids) in collaboration with the Saarland University Medical Center (PD Dr. Wolfgang Metzger).
Figure:
a) Free-fall apparatus for 3D high-speed imaging of particle-wall collisions,
b) pneumatic setup for analyzing the maximum liquid bridge length at high velocities, and
c) setup for analyzing the maximum liquid bridge length at low velocities:
1) vacuum needle, 2) hydrophilized glass plate with liquid film, 3) confocal sensor, 4) anti-vibration table, 5) high-speed cameras, 6) LED light sources, 7) pneumatic cylinder with attached particle, 8) plate with droplet, 9) pipette, 10) manometer, 11) throttle valve, and 12) Texture Analyzer® with a particle attached to the probe.
Research Projects
Description of the biomechanical properties of spheroids from human cells
Contact: Fabian Krull
Funding: DFG
Completed Research Projects
Surface structuring by cold-sprayed fine particles
Contact: Mustafa Bozoglu
Funding: DFG - B03 within CRC 926 - funding period 3
CRC 926 subproject A08: Dynamic interactions of particles with wetted structured component surfaces
Contact: David Strohner
Funding: DFG - A08 within CRC 926 - funding period 3
Dynamische Wechselwirkungen von Partikeln und Tropfen mit strukturierten Bauteiloberflächen
Contact: Fabian Krull
Funding: DFG - A08 in SFB 926 - Förderperiode 2
Selected Publications
Krull, F., Strohner, D., Antonyuk, S.: Experimental methods for model parameters in the Discrete Element Method, KONA Powder and Particle Journal (2025), https://doi.org/10.14356/kona.2026006
de Payrebrune, K.M., Schönecker, C., Antonyuk, S., Bilz, R., Krull, F., Noichl, I., Ripperger, S. & D. Strohner (2024): Interactions Between Particles and Surfaces. In: Aurich, J.C., Hasse, H. (eds) Component Surfaces. Springer Series in Advanced Manufacturing. Springer, Cham. https://doi.org/10.1007/978-3-031-35575-2_8
Krull, F., Strohner, D., Hering-Stratemeier, J., von Freymann, G., Antonyuk, S.: Measurements of micro particle rotation by applying marking points using additive manufacturing tools, Advanced Powder Technology 34 (2023) 104218 https://doi.org/10.1016/j.apt.2023.104218
Strohner, D., Antonyuk, S.: Experimental and numerical determination of the lubrication force between a spherical particle and a micro-structured surface, Advanced Powder Technology 34 (2023) 104173, https://doi.org/10.1016/j.apt.2023.104173
Hesse, R., Lösch, P., Antonyuk, S.: CFD-DEM analysis of internal packing structure and pressure characteristics in compressible filter cakes using a novel elastic-plastic contact model, Advanced Powder Technology 34 (2023) 104062, https://doi.org/10.1016/j.apt.2023.104062
Grohn, P., Oesau, T., Heinrich, S., Antonyuk, S.: Investigation of the influence of impact velocity and liquid bridge volume on the maximum liquid bridge length, Advanced Powder Technology 33 (2022) 6, 103630, https://doi.org/10.1016/j.apt.2022.103630
Hesse, R., Krull, F., Antonyuk, S.: Prediction of random packing density and flowability for non-spherical particles by deep convolutional neural networks and Discrete Element Method simulations, Powder Technology 393 (2021), 559-581 https://doi.org/10.1016/j.powtec.2021.07.056
Krull, F., Mathy, J., Breuninger, P., Antonyuk, S.: Influence of the surface roughness on the collision behavior of fine particles in ambient fluids, Powder Technology 392 (2021), 58-68 https://doi.org/10.1016/j.powtec.2021.06.051.