The random packing density of nearly spherical particles

Area of Science:

• Materials Science
• Statistical Mechanics
• Physics of Amorphous Materials

Background:

• Understanding the relationship between microscopic particle properties and macroscopic material characteristics is crucial for amorphous materials.
• Existing models primarily focus on spherical particles, limiting broader applications.

Purpose of the Study:

• To develop a general method for estimating the random packing density of non-spherical particles.
• To determine if non-spherical, yet sufficiently spherical, shapes pack more densely than perfect spheres.

Main Methods:

• Utilizing the known random packing configurations of spheres as a reference.
• Employing a perturbative calculation to linear order in particle deformation.
• Conducting analytical calculations and comparing with simulation data for numerical estimates.

Main Results:

• All sufficiently spherical particle shapes exhibit higher random packing densities compared to perfect spheres.
• Analytical calculations confirm denser packing for these shapes.
• Numerical estimates derived from sphere packing simulations align with simulation data for nonspherical particles.

Conclusions:

• Particle shape significantly influences the macroscopic density of amorphous materials.
• The developed method provides a pathway to predict packing densities for a wide range of particle shapes.
• This research offers fundamental insights into the packing behavior of non-spherical particles.