Dr Francois Guillard
Particles and Grains Laboratory
School of Civil Engineering
Granular materials such as sand and snow have the ability to behave both as solids (in sand dunes and snowdrifts) and as fluids (in hourglasses and avalanches). Dr François Guillard studies the properties and behaviours of granular materials and of brittle porous media, which have implications for industries including construction, mining, agriculture and pharmaceuticals.
"Granular materials are present everywhere in nature and in industry, but they exhibit extremely complex and rich behaviours that we don't yet fully understand. For example, no one knows quite how sandcastles hold together, how we can walk on sand or snow, or what happens inside a box of cereal.
"My research focuses particularly on the behaviour of granular materials when they are flowing, and how they transition between this behaviour and their solid state.
"I'm also studying how brittle porous media - such as rocks and sandstone, snow, volcanic ashes and even bones - behave under load and chemical degradation. I use puffed rice grains as a model material, for example, which can be brittle when dry but become soft and mushy when they stay too long in a liquid such as milk. These principles are of tremendous importance for both natural and artificial brittle porous materials that are compacted under load and soaked in water.
"In addition, I am involved in advancing the technology used to study granular materials. Currently we cannot see the behaviour of the grains below the surface, so I am developing X-ray radiography methods to study in real time and in three dimensions how granular materials flow internally.
"A better understanding of the properties and behaviours of such materials, combined with better experimental investigation techniques, can improve the safety and efficiency of numerous industrial processes, including the construction industry's use of sand, concrete and composite materials; the mining industry's methods of ore extraction and processing; the agricultural industry's storage, transport and processing of cereal grains; and the pharmaceutical industry's bulk handling and delivery of drugs in powdered form.
"I've been working in this field since 2010, and I joined the University of Sydney in 2013. Working here has greatly broadened my research interests and afforded me more direct access to the practical implications of my research. It also provides access to state-of-the-art infrastructure and facilities, which is of tremendous help in developing and addressing my research questions."
| Project title | Research student |
|---|---|
| Development of sensing and morphable robotic heads to improve navigation and locomotion of robots inspired by earthworms and plant roots in soil | Anas ABUSHAKER |
| Characterising fabric-density-stress relationships in clays under different loading conditions | Viet Khuyen BUI |
| Expected relations between stiffness and compaction in laboratory and field | Rohan LATIMER |
| Light Scattering Investigation of High Liquidity Clay Dynamic | Frank LIU |
Publications
Journals
- Guillard, F., Einav, I. (2024). Behavioural zone identification in rotary mills. Minerals Engineering, 212, 108711. [More Information]
- Bournival, G., Kim, Y., Shah, I., Anzoom, S., Guillard, F., Ata, S. (2024). Novel application of X-ray characterisation techniques in froth flotation for the study of bubble clusters. Minerals Engineering, 215, 108787. [More Information]
- Riley, D., Einav, I., Guillard, F. (2023). A constitutive model for porous media with recurring stress drops: From snow to foams and cereals. International Journal of Solids and Structures, 262-263. [More Information]
Conferences
- Riley, D., Einav, I., Guillard, F. (2023). Modelling Recurrent Stress Drops in Porous Media. Springer Series in Geomechanics and Geoengineering, : Springer Verlag.
- Baker, J., Bao, J., Guillard, F., Marks, B., Einav, I. (2019). Internal visualisation of flowing granular media using dynamic X-ray radiography. 13th International Conference on Bulk Materials Storage, Handling and Transportation (ICBMH 2019), Barton: Engineers Australia. [More Information]
- Guillard, F., Golshan, P., Shen, L., Valdes, J., Einav, I. (2017). Compaction dynamics of crunchy granular material. Powders and Grains 2017 - 8th International Conference on Micromechanics on Granular Media, Les Ulis, France: EDP Sciences. [More Information]
2024
- Guillard, F., Einav, I. (2024). Behavioural zone identification in rotary mills. Minerals Engineering, 212, 108711. [More Information]
- Bournival, G., Kim, Y., Shah, I., Anzoom, S., Guillard, F., Ata, S. (2024). Novel application of X-ray characterisation techniques in froth flotation for the study of bubble clusters. Minerals Engineering, 215, 108787. [More Information]
2023
- Riley, D., Einav, I., Guillard, F. (2023). A constitutive model for porous media with recurring stress drops: From snow to foams and cereals. International Journal of Solids and Structures, 262-263. [More Information]
- Riley, D., Einav, I., Guillard, F. (2023). Modelling Recurrent Stress Drops in Porous Media. Springer Series in Geomechanics and Geoengineering, : Springer Verlag.
2022
- Leighton, B., Guillard, F., Perez, K., Einav, I. (2022). Inverting the Paradigm: From Art to Granular Science. Leonardo, 55(5), 486-492. [More Information]
- Blatny, L., Berclaz, P., Guillard, F., Einav, I., Gaume, J. (2022). Microstructural Origin of Propagating Compaction Patterns in Porous Media. Physical Review Letters, 128(22). [More Information]
- Mejean, S., Guillard, F., Faug, T., Einav, I. (2022). X-ray study of fast and slow granular flows with transition jump in between. Granular Matter, 24(1), 26-1-26-15. [More Information]
2021
- Maranic, Z., Guillard, F., Baker, J., Einav, I., Marks, B. (2021). A granular thermometer. Granular Matter, 23(2), 19. [More Information]
- Jiang, S., Shen, L., Guillard, F., Einav, I. (2021). Characterisation of fracture evolution of a single cemented brittle grain using in-situ X-ray computed tomography. International Journal of Rock Mechanics and Mining Sciences, 145, 104835. [More Information]
- Guillard, F., Marks, B. (2021). Frictional hyperspheres in hyperspace. Physical Review E, 103(5), 52901. [More Information]
2020
- Mejean, S., Guillard, F., Faug, T., Einav, I. (2020). Length of standing jumps along granular flows down smooth inclines. Physical Review Fluids, 5(3), 1-22. [More Information]
- Dulanjalee, E., Guillard, F., Baker, J., Einav, I., Marks, B. (2020). Measuring grain size fractions of bidisperse granular materials using X-ray radiography. Optics Express, 28(20), 29202-29211. [More Information]
2019
- Jiang, S., Shen, L., Guillard, F., Einav, I. (2019). Fracture and fragmentation patterns within a single cemented glass bead under impact. International Journal of Impact Engineering, 131, 152-161. [More Information]
- Baker, J., Bao, J., Guillard, F., Marks, B., Einav, I. (2019). Internal visualisation of flowing granular media using dynamic X-ray radiography. 13th International Conference on Bulk Materials Storage, Handling and Transportation (ICBMH 2019), Barton: Engineers Australia. [More Information]
2018
- Jiang, S., Shen, L., Guillard, F., Einav, I. (2018). Energy dissipation from two-glass-bead chains under impact. International Journal of Impact Engineering, 114, 160-168. [More Information]
- Nadler, B., Guillard, F., Einav, I. (2018). Kinematic Model of Transient Shape-Induced Anisotropy in Dense Granular Flow. Physical Review Letters, 120(19), 198003-1-198003-5. [More Information]
- Jiang, S., Shen, L., Guillard, F., Einav, I. (2018). The effect of inter-grain contact material on the dynamic fracture of short glass bead chains under impact. Powder Technology, 339, 911-921. [More Information]
2017
- Guillard, F., Golshan, P., Shen, L., Valdes, J., Einav, I. (2017). Compaction dynamics of crunchy granular material. Powders and Grains 2017 - 8th International Conference on Micromechanics on Granular Media, Les Ulis, France: EDP Sciences. [More Information]
- Guillard, F., Marks, B., Einav, I. (2017). Dynamic X-ray radiography reveals particle size and shape orientation fields during granular flow. Scientific Reports, 7, 1-11. [More Information]
- Valdes, J., Guillard, F., Einav, I. (2017). Evidence That Strain-Rate Softening Is Not Necessary for Material Instability Patterns. Physical Review Letters, 119(11), 1-5. [More Information]
2016
- Marks, B., Guillard, F., Einav, I. (2016). High speed X-ray imaging of particulate flows. The 12th International Conference on Bulk Materials Storage, Handling and Transportation (ICBMH 2016), Barton, ACT: Engineers Australia.
- Liu, D., Shen, L., Einav, I., Guillard, F. (2016). Numerical Investigation on the Failure Behavior of Brittle Granular Chain under Impact. 2nd Australasian Conference on Computational Mechanics, Switzerland: Trans Tech Publications. [More Information]
- Wyburn, E., Marks, B., Guillard, F., Rognon, P., Einav, I. (2016). Particle shape effects on flowability of powder mixtures. The 12th International Conference on Bulk Materials Storage, Handling and Transportation (ICBMH 2016), Barton, ACT: Engineers Australia.
2015
- Guillard, F., Golshan, P., Shen, L., Valdes, J., Einav, I. (2015). Dynamic patterns of compaction in brittle porous media. Nature Physics, 11(10), 835-838. [More Information]
- Guillard, F., Forterre, Y., Pouliquenc, O. (2015). Origin of a depth-independent drag force induced by stirring in granular media. Physical Review E, 91(2). [More Information]
2014
- Guillard, F., Forterre, Y., Pouliquenc, O. (2014). Lift forces in granular media. Physics of Fluids, 26(4). [More Information]
2013
- Guillard, F., Forterre, Y., Pouliquen, O. (2013). Depth-Independent Drag Force Induced by Stirring in Granular Media. Physical Review Letters, 110(13), 138303-1-138303-5. [More Information]
2011
- Guillard, F., Pouliquen, O., Forterre, Y. (2011). Forces experienced by an object moving in granular medium. The 20th French Mechanics Congress 2011, France.
2010
- Fabre, B., Guillard, F., Solomon, M., Blanc, F., Sidorenkov, V. (2010). Structuring music in recorder playing: a hydrodynamical analysis of blowing control parameters. International Symposium on Music Acoustics (ISMA) 2010, Sydney, Australia: Curran Associates, Inc.
Selected Grants
2024
- A novel granular stress sensor for soil exploration, Einav I, Mazzolai B, Guillard F, Australian Research Council (ARC)/Discovery Projects (DP)
2022
- Physics-informed hydrodynamic model for clay across scales, Einav I, Guillard F, Soga K, Australian Research Council (ARC)/Discovery Projects (DP)
