Blue Firestorm: Fire ‘Tornado’ Burns Free from Soot

Scientists at the University of Maryland demonstrate a previously unobserved flame, a so-called blue whirl.

Researchers tried to combine the upward flow of hot air and the flame with a fast side wind. Similar spiral phenomenon occurs in nature such as wildfire or fuel fire. A blew whirl is a tiny and stable swirling flame that burns completely blue. Usually, blue whirls evolve from ordinary yellow fire whirls.