We investigate the properties of packings frictionless non-spherical particles utilizing a dynamic particle expansion technique. employ superquadric (superellipsoids), which allows us to explore how broad range shapes affect both macroscopic and local configurational system. smoothly transition from spherical possessing only translational degrees freedom large aspect ratio grains where rotational are highly important. demonstrate that degree anisotropy surface curvature have profound effect...

Several approaches to quantitative local structure characterization for particulate assemblies, such as structural glasses or jammed packings, use the partition of space provided by Voronoi diagram. The conventional construction spherical mono-disperse particles, which cell a particle is that its centre point, cannot be applied configurations aspherical polydisperse particles. Here, we discuss Set diagram particles in three-dimensional space. given composed all points are closer surface (as...

Rationale: There are at least four key pathophysiological endotypes that contribute to obstructive sleep apnea (OSA) pathophysiology. These include 1) upper-airway collapsibility (Pcrit); 2) arousal threshold; 3) loop gain; and 4) pharyngeal muscle responsiveness. However, an easily interpretable model examine the different ways extent which these OSA conventional polysomnography-defined severity (i.e., apnea–hypopnea index) has not been investigated. In addition, clinically deployable...

Investigating how tightly objects pack space is a long-standing problem, with relevance for many disciplines from discrete mathematics to the theory of glasses. Here we report on fundamental yet so far overlooked geometric property that disordered mono-disperse spherical bead packs have significant local structural anisotropy manifest in shape free associated each bead. Jammed packings several types experiments and simulations reveal very similar values cell anisotropy, showing linear...

The concept of "random loose packing" (RLP) has evolved through extensive study packings spheres, which resulted in an accepted definition as the loosest packing that can be obtained by pouring grains. We extend this consideration to nonspherical grains (ellipsoids) formed slow settling a viscous liquid, and perform detailed analysis structural properties resulting packings. find case spheres ellipsoid are generated for with high interparticle friction. However, unlike these cannot...

In particulate soft matter systems the average number of contacts Z a particle is an important predictor mechanical properties system. Using x-ray tomography, we analyze packings frictional, oblate ellipsoids various aspect ratios α, prepared at different global volume fractions ϕg. We find that monotonically increasing function ϕg for all α. demonstrate this functional dependence can be explained by local analysis where each described its fraction ϕl computed from Voronoi tessellation....

In particulate systems with short-range interactions, such as granular matter or simple fluids, local structure plays a pivotal role in determining the macroscopic physical properties. Here, we analyse metrics derived from Voronoi diagram of configurations oblate ellipsoids, for various aspect ratios $\alpha$ and global volume fractions $\phi_g$. We focus on jammed static frictional obtained by tomographic imaging discrete element method simulations. particular, consider packing fraction...

Soft gripping provides the potential for high performance in challenging tasks through morphological computing; however, design explorations are limited by a combination of difficulty generating useful models and use laborious fabrication techniques. We focus on class grippers based granular jamming that particularly difficult to model introduce "one shot" technique exploits multimaterial three-dimensional (3D) printing create entire grippers, including membrane grains, single print run....

The classical paradigm of the 'big magma tank' chambers in which melt differentiates, is replenished, and occasionally feeds overlying volcanos has recently been challenged on various grounds. An alternative school thought that such large, long-lived largely molten are transient to non-existent Earth's history. Our study stratiform chromitites Bushveld Complex-the largest magmatic body continental crust-tells, however, a different story. Several this complex occur as layers up 2 m thickness...

In textbook descriptions of Newton’s cradle, it is generally claimed that displacing one ball will result in a collision leads to another being ejected from the line, with all others remaining motionless. Hermann and Schmälzle, Hinch Saint-Jean, have shown realistic description more subtle. We present simulation cradle reproduces break-up line balls at first collision, eventual movement phase, good agreement our experimentally obtained data. The effect due finite elastic response balls,...

We have studied two-dimensional random packings of ellipses. When the aspect ratio is varied, a maximum packing fraction 0.895 found. discuss detailed dependence on ratio. The results are qualitatively similar to those Donev et al. [Science 303 990 (2004)], recently reported for ellipsoids in three dimensions.

We combine advanced image reconstruction techniques from computed X-ray micro tomography (XCT) with state-of-the-art discrete element method simulations (DEM) to study granular materials. This "virtual-laboratory" platform allows us access quantities, such as frictional forces, which would be otherwise experimentally immeasurable.

Particle scale modelling of comminution processes can provide significant insight into the flow particles, their breakage, effect slurry, wear and energy utilisation within these machines. The ability to use such models assist in faster lower cost design new devices improvement existing ones will be critical industry respond substantive challenges facing mineral processing next decade. These are reviewed drivers for change discussed. Understanding individual unit process performance needs...

Granular jamming is a popular soft actuation mechanism that provides high stiffness variability with minimum volume variation. Jamming particularly interesting from design perspective, as myriad of parameters can potentially be exploited to induce diverse variety useful behaviours. To date, grain shape has been largely ignored. Here, we focus on the use 3D printing expose variables related and size. Grains are represented by parameterised superquadrics (superellipsoids); four shapes...

A new multi-stage three-dimensional transient computational model to simulate powder bed fusion (L-PBF) additive manufacturing (AM) processes is presented. The uses the discrete element method (DEM) for flow simulation, an extended smoothed particle hydrodynamics (SPH) melt pool dynamics and a semi-empirical microstructure evolution strategy evolving temperature of non-spherical Ti-6Al-4V grains undergoing L-PBF. highly novel use both DEM SPH means that varied physics such as collisions...

Jamming Grippers are a novel class of soft robotic actuators that can robustly grasp and manipulate objects arbitrary shape. They formed by placing granular material within flexible skin connected to vacuum pump function pressing the un-jammed gripper against target object evacuating air transition jammed (solid) state, gripping object. However, due complex interactions between grain morphology shape, much uncertainty still remains regarding optimal constituent shapes for specific...