When "designer" particles like these are placed next to one another, the way mechanical energy travels through them is profoundly affected, according to new research. (Credit: Surajit Sen)

ScienceDaily (Aug. 9, 2011) — A University at Buffalo-led research team has developed a mathematical framework that could one day form the basis of technologies that turn road vibrations, airport runway noise and other “junk” energy into useful power.

The concept all begins with a granular system comprising a chain of equal-sized particles — spheres, for instance — that touch one another.

In a paper in Physical Review E this June, UB theoretical physicist Surajit Sen and colleagues describe how altering the shape of grain-to-grain contact areas between the particles dramatically changes how energy propagates through the system.

Under “normal” circumstances, when the particles are perfect spheres, exerting force on the first sphere in the chain causes energy to travel through the spheres as a compact bundle of energy between 3 to 5 particle diameters wide, at a rate set by Hertz’s Law. [Learn more]