GS00. Advanced modeling & simulation for discrete element methods

The Discrete Element Method (DEM) has become a de facto standard tool for simulating granular materials, and its utility is expected to increase further in both academic and industrial contexts. This general session aims to explore recent advancements in DEM and their applications, covering a wide range of topics such as solid-fluid coupling models, heat transfer models, fracture mechanics, powder mixing evaluation, packing and jamming simulations, finite element-discrete element coupling, colloidal particle dynamics, and high-performance computing. Through a series of engaging presentations and discussions, this session will provide a platform for leading researchers and scientists to exchange ideas, showcase their research, and foster potential collaboration.

MS01. Coupled discrete element method and computational fluid dynamics

This mini-symposium aims to bring together leading academic scientists and research scholars to exchange and share their experiences and research results on all aspects of complex granular systems using coupled DEM-CFD algorithms. The particles can be spherical, disk-shaped, or irregularly shaped elements. The numerical methods for CFD include the Finite Volume Method (FVM), Lattice Boltzmann Method (LBM), Smoothed Particle Hydrodynamics (SPH), and Material Point Method (MPM), among others. It provides a premier interdisciplinary platform to present and discuss the most recent innovations, trends, concerns, and practical challenges encountered, as well as the solutions adopted, in fields such as natural disasters, chemical engineering, soil/rock mechanics, ocean engineering, and more. This mini-symposium will enhance our understanding of the computational mechanics and engineering applications of complex granular systems involving solid particles and fluid.

MS02. Colloidal particle-laden flows

This symposium is dedicated to exchanging, discussing, and sharing the latest advancements in all aspects of flow involving colloidal particles. Topics include numerical modeling, particle-fluid, particle-particle, and particle-free interface interactions, non-equilibrium dynamics, rheology, and more. We welcome research at various scales—micro, meso and macro—across diverse colloidal systems such as colloidal suspensions, Pickering emulsions, and capillary suspensions.

MS03. Advanced DEM analysis in geotechnical engineering

DEM is recognized as a valuable numerical tool for solving engineering problems and has been widely applied to various geotechnical engineering issues, such as shear localization, liquefaction, and slope failures. It is also a powerful method for linking the micro-behavior of granular materials at the particle level to their macro-behavior as a continuum. Given the complexity of geomaterials, including irregular grain shapes, polydispersity, crushing/agglomeration and so on, further advancements in DEM modeling are also essential. This mini-symposium focuses on sharing cutting-edge research on DEM analyses in geotechnical engineering and exploring future directions together. The scope includes modeling soils and rocks with DEM, coupling with fluids using other numerical methods, analyzing multi-physics problems, improving computational algorithms, and utilizing high-performance computing. Topics related to validation and verification (V&V), including experimental studies, are also welcome.

MS04. Rheology of complex granular flows

This mini-symposium focuses on the granular flows involving complex particles and/or subject to extreme conditions. The complex particles may include non-spherical particles, flexible or deformable particles, or unusual meta-particles. The extreme conditions are referred to as high speed, high pressure, high temperature, or other noncommon environment, and an example of the granular flow under such condition is granular dispersion driven by a shock impact. The presented work is expected to give an in-depth understanding of the effects of particle properties (e.g. particle shape, flexibility, and self-propelling) on the granular flows by advancing rheological models, or to provide insights into the multiphase, multi-physical flow behaviors under the extreme conditions. You are welcome to submit an abstract to this mini-symposium, if your work falls in this scope. We look forward to a fruitful discussion in theoretical, numerical, and experimental development in the complex granular flows.

MS05. Particle shape and its role in industrial applications

This symposium provides a platform for academic and industrial researchers to share their contributions towards applications that consider the complexities of particle shape in pure DEM simulations and coupled simulations with SPH, LBM and CFD. Contributions in the following areas are welcome (while not restricted):

1. Particle shape representations eg. (SQ, Clumps, Polyhedra, Level-Set)
2. Contact detection algorithms: (a) spatial partitioning algorithms, (b) contact and force resolution
3. Multi-physics coupling considering particle shape
4. Industrial simulations
5. Reduced order model development from DEM data

MS06. Development and application of coarse-grained models for DEM

Discrete Element Method (DEM) has been widely used to simulate granular flows in various fields where the movement of particles is carefully tracked in a Lagrangian manner. One of the main advantages of DEM over a Eulerian model is that the individual particle properties and the inter-particle interactions can be directly considered. However, the price to pay is the extremely high computational cost which often hinders large-scale applications. Coarse grained models, which employ artificially scaled-up particles instead of original (small) particles, have become a popular choice to speed-up DEM simulation. Many scaling laws have been reported to replicate the bulk behaviour of original particles. This mini-symposium aims to bring together leading researchers and scientists working in this area to discuss (a) the recent developments of cutting-edge coarse-grained models and (b) their applications that involve large-scale simulations to foster a deeper understanding of granular flows. Topics that will be covered include (but not limited to):

1. Development of advanced coarse-grained models
2. Validation and verification of scaling laws
3. Real-life applications in industry and engineering
4. Large-scale simulation of granular flows

MS07. Recent advancements in fluidization modeling using DEM

Fluidization of granular materials plays a crucial role in numerous industrial processes and natural phenomena. The intricate interplay of driving forces and particle properties results in complex and diverse flows. Given that DEM and DEM-coupled techniques provide detailed particle-level information, they have become indispensable in fluidization research. This mini-symposium serves as a platform to discuss the recent advancements in fluidization modeling and simulation using DEM. We not only welcome fundamental modeling studies but also their practical applications. The topics to be covered are extensive and include, but are not limited to:

1. Fluidization by hydrodynamic forces (gas/liquid/gas-liquid mixtures)
2. Fluidization by mechanical vibrations.
3. Fluidization under the influence of attractive/repulsive inter-particle forces (e.g., liquid bridge and electrostatic).
4. Fluidization of non-spherical particles. Fluidization of poly-dispersed particles.
5. Fluidization in nature.
6. Resolved and unresolved DEM-coupled models.

MS08. Data-driven modeling for granular and multiphase flows

This mini-symposium is dedicated to bringing together esteemed experts who are advancing data-driven modeling in the realm of granular and multiphase flows. Recent advancements in machine learning and data-driven approaches have provided novel insight into the modeling and simulation of various particulate systems. The mini-symposium warmly welcomes submissions focused on recent developments and applications of innovative data-driven approaches for granular and multiphase flows. Topics of interest include but are not limited to:

1. Data-driven constitutive modelling of granular materials;
2. Physics-informed learning for computational fluid/granular mechanics;
3. System dynamics identification in powder processes;
4. Machine/Reinforcement learning for calibrating parameters of granular materials;
5. Intrusive/Non-intrusive reduced-order modelling for real-time simulation of granular phenomena;
6. Innovative data-driven/physics-based surrogate modeling of powder processes;
7. Digital twins for next-generation powder industries.

MS09. Novel improvements and applications of DEM for industry

The Discrete Element Method (DEM) will and has already begun to revolutionise the way industrial powder handling equipment is designed and physical phenomena are understood in a huge variety of use cases, from large particle sizes in mining and geotechnics to the finest pharmaceutical powders. Despite numerous remaining challenges in DEM, successful and practical applications are already shifting from theoretical research to practical industrial use. This mini-symposium will provide a place for these problems to be discussed, but also the successes to be celebrated.The primary objective of this mini-symposium is to provide a place for DEM engineers and researchers to exchange knowledge and ideas on the current and future state of DEM application in industry. Connecting DEM experts from various companies and universities with successful applications of DEM in a variety of different fields will allow further collaborations to flourish and allow cross pollination between industrial sectors to inspire novel approaches to unsolved problems. Industrial case studies will illustrate the innovative impact of DEM across different sectors.The range of talks will focus on highlighting progress in industry driven by recent advancements in commercial and open-source DEM software, the emergence of novel start-up companies tackling industrial problems with DEM, and innovative academic solutions addressing the challenges of industrial applications. Key issues to discuss will include computation time, calibration, validation, and standardisation in the application of DEM to ensure a targeted event that will provide the highest value to attendees.

MS10. DEM and coupled Sims: calibration of industrial applications

DEM and DEM-Coupled simulations have become largely embraced as useful tools to study and predict the behavior of powders and granular bulk solid materials in industrial processes. In theory, the DEM parameters should represent the material properties at the particles level. However, in the industrial scale, this task is difficult or near impossible to account for each particle shape, size, and surface property. To overcome these challenges, an upscaled or coarse-grained representation of the material is typically utilized. Therefore, a calibration process is used to reproduce the macroscopic or bulk behavior. DEM parameters obtained through this process using laboratory scale testing or physical modeling can differ significantly from the theoretical values. The calibration between the particle bulk behavior must be properly determined beforehand to provide usable, reliable, and validated results. This mini symposium focusses on the methods used for the calibration of industrial problems as well as their application in industry or the natural field. The objectives of the presentations include but are not limited to:

1. Development of laboratory testing or physical modeling for DEM, DEM coupled problems
2. Technologies for the calibration of industrial problems
3. Case Studies using real world material testing for applications in the industry fields and natural fields

MS11. Industrial application of DEM & CFD-DEM

Many industrial processes involve the handling of particles, such as in catalyst manufacturing, mining, or diaper production. In some cases, these processes are even dominated by particle physics, making it essential to have a thorough understanding of the process and the underlying unit operations to remain cost-effective and competitive. Despite the widespread application and fundamental importance of particle processes, their design and prediction often rely on empirical knowledge. The Discrete Element Method (DEM) and Computational Fluid Dynamics coupled with DEM (CFD-DEM) have addressed some of these challenges and hold promise for future advancements. This session will focus on various aspects that enable the industry to tackle future challenges, including specific contact models (e.g., for pastes), new calibration routines (e.g., for cohesion), and coupling approaches (e.g., with FEM or models for magnetic and electric fields), as well as examples of successful industrial-scale process predictions.

MS12. DEM modelling in the field of railway systems

Granular materials play an important role in railway systems. Ballasted tracks have been used worldwide since the beginning of railways. DEM modelling of the ballast bed is an active and well-established field of research. The simulation of classical laboratory tests, such as triaxial test, cyclically loaded box tests or sleeper pull out tests, is challenging amongst others due to the complex shape of the single stones. Consequently, shape modelling of ballast has received much attention, with clumps of spheres, polyhedral and other complex shape models being applied. Other challenges of DEM simulations of ballast are the physically correct contact modelling, including fragmentation of stones during loading, and the high number of particles involved when longer track sections are considered. Nevertheless, the insights gained from DEM modelling are very valuable as they allow for studying the impact of new track components as e.g. geogrids, under sleeper pads, under ballast mats during operation or the tamping process when maintaining the track.
Another field of research is the extremely loaded contact between wheels and rails which is determined by complex tribological processes. Typically, so-called third body layers (3BL) are embedded between wheels and rails, consisting of liquids (e.g. water), solid particles (e.g. wear particles) or mixtures. Such 3BLs have a strong influence on the adhesion conditions in the wheel-rail interface. Some 3BLs can cause (ultra-)low adhesion conditions interfering with traction and braking. This can be overcome by wheel-rail sanding where sand grains are blasted into the wheel-rail contact. Sand grains will partially crush when entering the contact, causing plastic deformations on wheel and rail surfaces. DEM modelling of the sanded wheel-rail contact is relatively new. Together with extensive experimental tests, it contributes to a better understanding of the underlying physical mechanisms of adhesion increase.
Submissions are encouraged covering all railway related DEM topics.

MS13. Non-spherical particles in industrial applications

In most industrial applications, granular materials are ubiquitous and most of them come with non-spherical shapes, ranging from micron-sized powders to millimetre or even centimetre-sized minerals and rocks. These irregularly shaped granular materials show different flow behaviours compared to materials with more spherical shapes, such as glass beads, sand and iron pellets. With the growth of computational power in recent decades and advancements in DEM (Discrete Element Method) contact models, it is now possible to incorporate arbitrary particle shapes in DEM simulations using various methods at the single particle scale. These methods include multi-spheres/clumps, (super-)ellipsoids, super-quadrics, and polyhedral particles. However, all of these methods are approximations of real particle shapes, each with varying degrees of accuracy. The application of these approximated shapes is typically ad-hoc across different processes, presenting a significant challenge in modelling industrial processes with non-spherical particles while balancing computational cost and accuracy.
This mini-symposium aims to provide a platform for scientists and engineers to discuss the latest advancements in modelling both industrial and academic applications that involve particle shapes. The main focus will be on the accuracy and practicality of modelling particle shapes, including particle shape descriptors, generation methods, calibration, verification, and validation techniques and scale of applications. Submissions are encouraged on topics including, but not limited to:

1. Capturing shape properties of particles
2. Packing behaviour of irregularly shaped particles.
3. Granular flow
4. Mixing and segregation
5. Penetration process
6. Small (lab) to large (industrial) scale applications

We look forward to your contributions and to stimulating discussions on these exciting topics.

MS14. DEM for pharmaceutical and battery manufacturing

Discrete Element Methods (DEM) has been widely used in modelling and simulating particulate interactions within various industrial sectors such as pharmaceuticals, food, energy, and metallurgy. This mini-symposium aims to address the challenges and opportunities in applying DEM for manufacturing pharmaceutical products and batteries, and provides a platform for sharing experience and recent advances in DEM application. It will offer attendees valuable insights into how advanced DEM simulations are being adapted and applied in practical settings, promoting innovation in the field of particulate product manufacturing. A primary concern in employing DEM at an industrial level is the balance between computational speed and model accuracy. Full-scale operational units in sectors, like pharmaceutical and food manufacturing, require simulations that capture complex multi-physics interactions within processes in a reasonable time scale. These processes necessitate detailed modelling of particle interactions under varying conditions, which can dramatically increase computational load. Moreover, incorporating complicated multi-physical models: such as breakage, electrostatic, heat and mass transfer models into DEM simulations introduces additional computational challenges. Achieving a balance between computational feasibility and the level of accuracy is needed for effectively modelling of real-world applications. This mini-symposium focuses on recent advancements in modelling particulate product manufacturing in the pharmaceutical and battery industries, which may include but not limited to unit operation modelling, microstructure predictions, and digital twins.

MS15. Join our open network for discrete element simulations

Particle-based simulations are used to model various materials such as sand, food grains, pharmaceuticals, and bulk materials. The Discrete Element Method (DEM) is a key simulation technique applied across multiple disciplines, leading to diverse approaches and many DEM software options. Selecting the right DEM software is often challenging, even for experienced researchers, due to a steep learning curve. Open-source packages are advantageous for research as they are free, promote knowledge sharing, reproducibility, and avoid the “black box” issues of commercial platforms. This Action aims to unify knowledge across DEM communities.
A European COST network, ‘Open Network on DEM Simulations (ON-DEM),’ was recently funded to advance DEM capabilities by sharing developments, promoting best practices, providing simulation examples, and offering training for early career researchers. The network has five themes:

1. addressing large-scale industrial and engineering problems
2. incorporating physics for more realistic simulations
3. using big data and visualization tools for faster analysis
4. standardizing best practices
5. increasing the commercial use of DEM codes

Each theme corresponds to a Working Group tackling current challenges in DEM simulations. A sixth group focuses on dissemination and engagement with stakeholders.
This mini-symposium will introduce the ON-DEM COST network, with talks open to anyone interested in open-source particle simulations. Suggested topics include open-source particle codes, industrial applications, coupling with fluid/solid solvers, optimizing simulations, and standardizing visualization tools.

MS16. Using DEM To Enhance Education

The primary objective of this mini-symposium is to explore innovative approaches to integrating DEM into the teaching of university and professional courses. Given the increasing complexity of real world problems and the need for robust, simulation-based learning tools, DEM offers significant potential to enhance educational outcomes across a range of fields. This session aims to gather educators, researchers, and practitioners to share experiences, methodologies, and tools that leverage DEM for instructional purposes. Potential Themes and Topics

1. Curriculum Integration: Strategies for incorporating DEM into undergraduate and graduate engineering programs.
2. Case Studies: Examples of successful DEM-based projects and their impact on student learning and engagement.
3. Software and Tools: Discussion of open-source and commercial DEM software that can be utilized in an academic setting.
4. Interactive Learning: Approaches for creating interactive and hands-on learning experiences using DEM.
5. Assessment and Outcomes: Methods for evaluating the effectiveness of DEM in enhancing student understanding and skills.

We anticipate this mini-symposium will attract a diverse audience interested in the pedagogical benefits of DEM, promoting a vibrant exchange of ideas and best practices.

MS17. Application of DEM in composite materials

This symposium aims to explore the cutting-edge applications of the Discrete Element Method (DEM) in understanding and predicting the mechanical properties and fracture analysis of composite materials. As composites continue to play a pivotal role in advanced engineering applications, understanding their complex mechanical behavior and failure mechanisms is essential. DEM offers a powerful tool for simulating and predicting these behaviors, particularly in situations where experimental and conventional numerical methods may be inadequate. The symposium will focus on several key objectives, starting with overcoming the challenges in calibrating DEM models when laboratory data is insufficient or unavailable, a common issue in the study of composites. Participants will explore advanced strategies for calibration, ensuring that DEM models can accurately replicate the mechanical behavior of these materials. The discussion will extend to the detection and modeling of various fracture modes, such as debonding and delamination, which are critical in determining the failure mechanisms of different composite materials. The symposium will also cover the determination of mechanical properties using DEM, offering insights into how these properties can be reliably predicted and analyzed across different composite systems. A significant portion of the symposium will be dedicated to linking micro and macro mechanical properties, facilitating a better understanding of how material structure at small scales influences overall behavior. Finally, the symposium will delve into the best strategies for modeling the matrix/reinforcement interface, a key factor that influences the overall mechanical behavior of composites. By bringing together experts from academia and industry, this symposium aims to foster collaboration and share the latest research and methodologies in the field. The insights gained from this symposium are expected to lead to more accurate and reliable applications of DEM in the study of composite materials, ultimately contributing to advancements in material science and engineering.

MS18. DEM with deformable particles

Traditionally, Discrete Element Methods (DEM) have been designed under the assumption that particles retain their shape and size, or only experience minimal deformations that are negligible in simulations. However, in many industrial processes, particles undergo significant changes in shape and size—such as swelling, shrinkage, and bending—or experience notable deformation. Accurately capturing these changes is crucial for better predicting their behavior during these processes. This mini-symposium aims to address the challenges of modeling deformable particles using DEM. We welcome contributions on recent advancements in this area, including, but not limited to, model development and applications related to particle swelling, shrinkage, flexible particles, particle breakage or fragmentation, and sintering.

MS19. Modeling soft deformable particles

The study of soft particles is a diverse and rapidly advancing field within materials science and the physics of complex systems. These particles encompass a wide range of materials, including hydrogels, polymers, colloids, emulsions, and plant cells. Modeling these materials and understanding their mechanical properties is critical, with broad implications across multiple scientific disciplines. Despite their varied physical properties, what unites these materials is their shared capacity for significant deformation. This deformation arises from both collective particle rearrangements and changes in particle volume or shape under external and internal stresses. These characteristics greatly influence the space-filling behavior of soft-particle systems and, consequently, their frictional and flow behavior, distinguishing them from hard-particle packings.
The standard Discrete Element Method (DEM) is unsuitable for simulating soft deformable particles due to its lack of bulk degrees of freedom. Several numerical models have already been developed for deformable particles, including hybrid methods combining DEM with continuum methods such as the Finite Element Method (FEM), Material Point Method (MPM), and Peri-dynamics. Similarly, methods based on DEM with surface degrees of freedom or uniform-strain assumptions have also been proposed. The goal of this mini-symposium is to focus on the technical computational approaches for simulating soft deformable particles, as well as their applications to general and specific problems, such as packing, shear flow, compaction, jamming transitions, and fluidization.

MS20. Novel contact models and advanced physics

The contact model used in a DEM simulation describes the mechanics of the interaction between the particles and is therefore a vital element to get right for a successful outcome. With the evolution of hardware allowing faster and larger simulations, the use of more complex particle shapes (polyhedral, superquadrics and others) are gaining popularity. Also emerging are the development of complex particle models to simulate complex particle behaviours, including cohesive powders, abradable particles and deformable particles. Whilst the contact models for spherical based contacts are well established, there is a need to develop contact models that allows more accurate modelling of particle physics and take into account particle shapes and complex particle interaction forces. This mini-symposium aims to promote the discussion on new particle and contact models needed to take into account this new reality and the current needs of DEM simulations.