Effect of flake shape on packing characteristics of popped popcorn

• Number of flakes to fill a tub agreed well between experiments and simulations.
• Packing fraction varied from ρ = 0.14–0.28.
• Fewer popcorn pieces were required to fill the tub as unilateral shape decreased.
• 36.9% bilateral +63.1% multilateral minimized the number of flakes to fill the tub.

The purpose of this study was to determine to role of flake shape on the packing characteristics of popped popcorn. Unilateral, bilateral, and multilateral popcorn flakes, named for the direction of expansion of the popcorn flake, were digitized and packed into a virtual conical frustum-shaped container using a digital packing algorithm to simulate particle packing. Corresponding laboratory experiments were also conducted. Number of flakes required to fill the container agreed between simulated and laboratory experiments (r = 0.996; p < 0.0001) and ranged from about 340 for 50% bilateral +50% multilateral to >600 for 100% unilateral. Statistical modeling revealed 36.9% bilateral +63.1% multilateral would minimize the number of flakes required to fill the container. Packing fraction varied from ρ = 0.14 for 10% unilateral +75% bilateral +15% multilateral to ρ = 0.28 for 100% unilateral shape. These results offer insights into the packing characteristics of irregularly-shaped materials.