When you see the words “perfect packing” are you thinking of getting ready for that vacation and neatly folding your swimming costume and other clothes into your suitcase? Or are you thinking of the worst-suitcase scenario when you’re packing after your vacation and trying to get that didgeridoo, boomerang, and other assorted odd-sized souvenirs into that same suitcase, finding you have a problem, and having to buy another suitcase or ship the odd-shaped ornaments by other routes?
I won’t bore you with the story of trying to be smart, shipping my business clothes back to the UK in advance of a vacation, and then subsequently just recovering aforesaid business attire shortly before it was destined for a Kentucky incinerator….
The above problems are a reflection of those that manufactures have to go through every day. How much pasta can you get into that box? How much popcorn can you load into a container prior to the cinema movie? In the 1500’s a similar problem bothered Sir Walter Rayleigh (Rawle-ee, of course, being the correct pronunciation) – what’s the best way of stacking cannonballs to maximize the space utilization? More pertinent problems relate to forming dense ceramic structures that pack perfectly without voids or agglomerates (potential areas of weakness or breakage) something we touched on in an earlier webinar:
Now particle packing affects among other things:
- Flow through a system (liquid through solids – oil industry; gas through solid: cement – Blaine; Carmen-Kozeny equation; flow of heat/heat transfer etc)
- Flowability (and thus rheology for solid in liquid systems)
- Segregation – from size and shape effects – and thus settling
- “Density” – apparent/tap/absolute/real
Rheology is dramatically affected by packing – indeed it’s possible to get more oil in an oil-in-water emulsion without affecting the viscosity simply by playing with the particle size distribution. My forthcoming webinar “In pursuit of perfect packing* (* with apologies to the book title “The Pursuit of Perfect Packing” by Tomaso Aste and Denis Weaire IoP (2000)) explores in more detail this favorite interest of mine initially stimulated by 2 things:
- Tackling packing of crystals as a first year undergraduate
- Articles by Martin Gardner in Scientific American if I recall correctly and summarized in his “ Further Mathematical Diversions” (another book never removed from the library before it was sold)
In this webinar, I’ll be covering the cannonball story and the Kepler conjecture leading onto packing of spheres and also ideal theoretical particle size distributions for most dense packing (minimum void space). Register for the webinar on: “In pursuit of perfect packing“
Hope to see you there!