Scaling behavior of cohesive self-gravitating aggregates

Azéma, Émilien; Sánchez, Paul; Scheeres, Daniel J.

doi:10.1103/physreve.98.030901

Cited by 13 publications

(6 citation statements)

References 44 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The discrete element method (DEM) proposed by Cundall and Strack [25] has led to new possibilities for modelling interactions and processes between a large number of individual objects. The method has been applied in numerous areas of science and technology, including physics [26], pharmaceutical science [27], civil engineering [28], and agricultural engineering [29]. This method is a very promising tool for modelling biomass post-harvest processing, including handling [30][31][32], compaction [33], and testing biomass bulk properties [34].…”

Section: Introductionmentioning

confidence: 99%

Breakage Strength of Wood Sawdust Pellets: Measurements and Modelling

Horabik¹,

Bańda²,

Józefaciuk³

et al. 2021

Materials

View full text Add to dashboard Cite

Wood pellets are an important source of renewable energy. Their mechanical strength is a crucial property. In this study, the tensile strength of pellets made from oak, pine, and birch sawdust with moisture contents of 8% and 20% compacted at 60 and 120 MPa was determined in a diametral compression test. The highest tensile strength was noted for oak and the lowest for birch pellets. For all materials, the tensile strength was the highest for a moisture content of 8% and 120 MPa. All pellets exhibited a ductile breakage mode characterised by a smooth and round stress–deformation relationship without any sudden drops. Discrete element method (DEM) simulations were performed to check for the possibility of numerical reproduction of pelletisation of the sawdust and then of the pellet deformation in the diametral compression test. The pellet breakage process was successfully simulated using the DEM implemented with the bonded particle model. The simulations reproduced the results of laboratory testing well and provided deeper insight into particle–particle bonding mechanisms. Cracks were initiated close to the centre of the pellet and, as the deformation progressed, they further developed in the direction of loading.

show abstract

Section: Introductionmentioning

confidence: 99%

Breakage Strength of Wood Sawdust Pellets: Measurements and Modelling

Horabik¹,

Bańda²,

Józefaciuk³

et al. 2021

Materials

View full text Add to dashboard Cite

show abstract

“…Later on, in 2014, a first use of a Non Smooth approach was proposed to study regolith processes [39]. More recently, in 2018, the Contact Dynamics (CD) method, was applied to analyze the strength properties of self-gravitating aggregates of spheres [40]. A year later, Ferrrari, et al [41,42] used the same method to study asteroid aggregation problems with angular particles.…”

Section: Introductionmentioning

confidence: 99%

A contact dynamics code implementation for the simulation of asteroid evolution and regolith in the asteroid environment

Sánchez

Renouf

Azéma

et al. 2021

Icarus

Self Cite

View full text Add to dashboard Cite

Over the last decades, simulations by discrete elements methods (DEM) have proven to be a reliable analysis tool in various domains of science and engineering. By providing access to the local physical mechanisms, DEM allows the exploration of microscopic based phenomena related to particles properties and interactions in various conditions and to revisit constitutive equations consequently. The growing computer power and memory now allow us to handle large collections of grains of various shapes and sizes by DEM simulations and in particular, it offers new perspectives in the exploration of the behavior of asteroids seen as self-gravitating and cohesive granular aggregates. In this paper we describe the Contact Dynamics (CD) method, a class of DEM based on non-smooth mechanics, and its implementation in the open-source software LMGC90. In contrast to more classical approach, Hard-and Soft-Sphere DEM, the CD method is based on an implicit time integration of the equations of motion and on a non-regularized formulation of mutual exclusion between particles. This numerical strategy is particularly relevant to the study of dense granular assemblies (even of large size) because it does not introduce numerical artefacts due to contact stiffness. So that it can be used for Small Body research, we implement a parallelised kd-tree and monitor the performance of the code as it simulates a number of granular systems. We provide examples of the simulation of the accretion of self-gravitating aggregates as well as their rotational disruption. We use the routines at our disposal in the code to monitor their behaviour through the entire evolution and find agreement with previous research.

show abstract

“…This way of writing P as a function of Z, φ , and σ is, in fact, very common and has been successfully applied in different contexts. For example, it has been used to relate the bulk properties of an assembly to the elastic contact properties 71,72 , or to link the macroscopic cohesive strength to the cohesive behavior between the interface of particles in contact 29,73 . The Equation ( 6) reveals the active role of the evolution of the microstructure in the evolution of P with φ .…”

Section: A Compaction Equationmentioning

confidence: 99%

“…This approach is relatively straightforward and allows one to simulate 3D packing composed of a large number of aggregates. However, a major drawback is that the deformable particles often present a plastic behavior at large strain, and their characterization can be complex depending on the imposed numerical parameters (e.g., size of primary particles or in-teraction laws) 29,30 . In contrast, DEM-FEM strategies have the advantage of being closely representative both in terms of geometry and bulk properties of the particles.…”

Section: Introductionmentioning

confidence: 99%

Three-dimensional compaction of soft granular packings

Cárdenas-Barrantes¹,

Cantor²,

Barés³

et al. 2021

Preprint

Self Cite

View full text Add to dashboard Cite

This paper analyzes the compaction behavior of assemblies composed of soft (elastic) spherical particles beyond the jammed state, using three-dimensional non-smooth contact dynamic simulations. The assemblies of particles are characterized using the evolution of the packing fraction, the coordination number, and the von Misses stress distribution within the particles as the confining stress increases. The packing fraction increases and tends toward a maximum value close to 1, and the mean coordination number increases as a square root of the packing fraction. As the confining stress increases, a transition is observed from a granular-like material with exponential tails of the shear stress distributions to a continuous-like material characterized by Gaussian-like distributions of the shear stresses. We develop an equation that describes the evolution of the packing fraction as a function of the applied pressure. This equation, based on the micromechanical expression of the granular stress tensor, the limit of the Hertz contact law for small deformation, and the power-law relation between the packing fraction and the coordination of the particles, provides good predictions from the jamming point up to very high densities without the need of tuning any parameters.

show abstract

Scaling behavior of cohesive self-gravitating aggregates

Cited by 13 publications

References 44 publications

Breakage Strength of Wood Sawdust Pellets: Measurements and Modelling

Breakage Strength of Wood Sawdust Pellets: Measurements and Modelling

A contact dynamics code implementation for the simulation of asteroid evolution and regolith in the asteroid environment

Three-dimensional compaction of soft granular packings

Contact Info

Product

Resources

About