2012 BFY Abstract Detail Page
Previous Page |
New Search |
||W21 - Granular Materials: A Low-Tech Advanced Lab Exercise
||Can an Advanced Lab be low-tech, but still be productive & fun? Consider some of the following questions:
- How many crates will fit in your truck?
- How much does your box of (cereal, candy, grain, marbles, push-pins, ...) settle during shipment?
- Can you use only half of the package of dry soup mix, and still have both peas and spice in your soup?
- How many jelly beans does that giant jar in the drug store REALLY contain? Why are the Brazil Nuts all at one end of the can?
These are the types of questions that studies of Granular Materials address. Experiments on Granular Materials can help answer these and other questions.
A granular material can be defined as any loosely interacting collection of (usually) solid particles. Depending on the conditions, a granular material can be best described as a solid, or as a fluid, or as a gas, or in some case not adequately as any of these, which makes this both an interesting and difficult field of study. Granular Materials is an area of study in physics that, while it has many important applications, is poorly understood on a fundamental level, and has become a recent area of much interest.
This is one area in which the experiment is not only more fun, but MUCH simpler than the associated calculation/modeling - even if you stay with monodisperse (all the same), spherical particles, the calculations can be daunting (especially in 3 dimensions). However, many of the measurements are simple (in concept), but still have a number of interesting experimental and measurement challenges.
Experiments can range from the basic (Angle of Repose of a pile of granules - think piles of sand), to the complex and not yet fully understood (Longitudinal and Axial Segregation in the 'Rotating Drum'). Depending on the granules used, ANY experiment your students do may be completely new, as there is such as great range of sizes, shapes and types of 'granules', including such things as bubbles and foams.
We will do some basic measurements (Angle of Repose, Flow Rate, Packing Fraction), and touch on the more complex situations, in particular a version of the Rotating Drum. Most likely, we will be using various shapes of foodstuffs (cereal), so in principle we can even eat our results when we are done (though that is not really recommended)!
Download the Workshop Document
Northeastern Illinois Univ.