In this work, a two-dimensional numerical fluid model is developed for a partially packed dielectric barrier discharge (DBD) in pure helium. Influence of packing on the discharge characteristics is studied by comparing the results of DBD with partial packing with those obtained for DBD with no packing. In the axial partial packing configuration studied in this work, the electric field strength ...

We report a new periodic structure of the cylinder packing. All the cylinders are congruent and the length of the cylinders are infinite and their directions are restricted to only six directions of 〈110〉. Each cylinder is fixed by cylinders of other directions, so that the whole structure sustains mechanical stability. The packing density equals to

We present the first systematic algorithm to estimate the maximum packing density of spheres when the grain sizes are drawn from an arbitrary size distribution. With an Apollonian filling rule, we implement our technique for disks in 2d and spheres in 3d. As expected, the densest packing is achieved with power-law size distributions. We also test the method on homogeneous and on empirical real ...

BACKGROUND AND PURPOSE Five to 60% of coiled brain aneurysms recanalize, generally because of coil compaction. In vitro exclusive use of complex-shaped coils allows better packing of the aneurysmal sac and the neck as compared with helical coils. We report a single-center, prospective study using complex coils. Safety, packing density, and recanalization rate were evaluated. MATERIALS AND MET...

We design a vehicle with a steering system made of two independently rotatable wheels on the front. We quantify the effectiveness of the steering system in the mobility and maneuverability of the vehicle running in a box containing a layer ping-pong balls with a packing density 0.8, below the random close packing value 0.84 in 2D. The steering system can reduce the resistance exerted by the jam...

Obtaining general relations between macroscopic properties of random assemblies, such as density, and the microscopic properties of their constituent particles, such as shape, is a foundational challenge in the study of amorphous materials. By leveraging existing understanding of the random packing of spherical particles, we estimate the random packing density for all sufficiently spherical sha...

We introduce an algorithmic framework for tuning the spatial density of disks in a maximal random packing, without changing the sizing function or radii of disks. Starting from any maximal random packing such as a Maximal Poisson-disk Sampling (MPS), we iteratively relocate, inject (add), or eject (remove) disks, using a set of three successively more-aggressive local operations. We may achieve...

Self-assembled supramolecular organic liquid crystal structures at nanoscale have potential applications in molecular electronics, photonics, and porous nanomaterials. Most of these structures are formed by aggregation of soft spherical supramolecules, which have soft coronas and overlap each other in the packing process. Our main focus here is to study the possible packing mechanisms via molec...

The volume changes of lithium and sodium under pressure are discussed with respect to the packing density of the atoms and their valence. In densely packed Li I (bcc), Li II (fcc), and Li III (α-Hg type), valence increases from 1 at ≈ 5 GPa to ≈ 2.5 at 40 GPa. The maximum valence 3 is attained in Li IV (body-centered cubic, 16 atoms per cell, packing density q = 0.965) at 47 GPa. In densely pac...

We numerically study structural properties of mechanically stable packings of hard spheres (HS), in a wide range of packing fractions 0.53 ≤ ϕ ≤ 0.72. Detailed structural information is obtained from the analysis of orientational order parameters, which clearly reveals a disorder-order phase transition at the random close packing (RCP) density, ϕc ≃ 0.64. Above ϕc, the crystalline nuclei form 3...