Scientists have discovered a new type of fire tornado called the "blue whirl." But unlike its counterparts, which pose a threat to life and property, the "blue whirl" is surprisingly eco-friendly and can even help in pollution and oil spills.
According to the study published in the journal Proceedings of the National Academy of Sciences, scientists discovered the new type of flame while combining rising heat and turbulent winds.
The "blue whirl" flame is a refined flame that consists of a core flame while rotating columns of air surround it. The result looks like a mini blue tornado spinning like a top.
“Blue whirls evolve from traditional yellow fire whirls. The yellow color is due to radiating soot particles, which form when there is not enough oxygen to burn the fuel completely,” said Elaine Oran, co-author of the study, via UMD Right Now.
Oran further explained that the fire's blue hue is an indication that the flame has enough energy to complete combustion in a cleaner way without any soot and lower carbon emission.
To investigate the blue whirl's combustion property on water and, for the first time, its practical application, the researchers created a lab-simulated oil spill. Results showed that using blue flame is more efficient than current practices, such as corralling thick layers of crude oil on the water surface.
"In our experiments over water, we’ve seen how the circulation fire whirls generate also helps to pull in fuels. If we can achieve a state akin to the blue whirl at larger scale, we can further reduce airborne emissions for a much cleaner means of spill cleanup,” said co-author Michael Gollner.
Huahua Xiao, assistant research scientist in the Clark School's Department of Aerospace Engineering, adds that the "blue whirl" flame is "very quiet and stable without visible or audible signs of turbulence."
“A fire tornado has long been seen as this incredibly scary, destructive thing. But, like electricity, can you harness it for good? If we can understand it, then maybe we can control and use it,” Gollner said.
The study says the new discovery could lead to better and more efficient ways in cleaning oil spills as well as added understanding of fluid mechanics.