Washington: A new Canadian research has found that subtle differences in wind and water can produce icicles with strange shapes.
Using an indoor icicle-making machine, the researchers have challenged a mathematical theory claiming that all icicles tend to grow towards the idealized cone-like shape they have in cartoons.
"The ideal icicle, the mathematically minimum icicle, is elegant and beautiful. But the reality has turned out to be much more complicated," Fox News quoted icicle grower Stephen Morris, of the University of Toronto, as saying.
At the University of Arizona, Tucson, Martin Short claimed last year that all icicles tend to grow towards an ideal shape and provided the physics rules needed to explain this shape.
But Morris, who was not convinced by the seven photographs of icicles Short, looked at to test this theory, built a device to grow 93 icicles under a variety of different conditions and different water sources.
At the top of the device, a nozzle sprinkled water onto a growing icicle hanging from a platform that rotated rotisserie-style. The rotation, too slow to affect the shape of the icicle, helped to expose all sides of the growing icicle equally to a fan’s cold breeze.
When fed by pure distilled water, the foot-and-a-half long icicles often formed points that resembled Short’s predictions.
But the icicles were most cone-like not when the air was still, as theory predicted, but when the air was moving. In still air, the icicle often grew legs, forking into multiple tips.
The type of water also affected the shape. Icicles grown from tap water tended to bend and bulge.
The findings were published online to arxiv.org.