We have written a number of times about fire whirls and fire tornadoes observed in wildfires. They can be very impressive and very dangerous…. except when they are created in a laboratory as in the video below. A tip for viewers… after about a minute and a half, there is very little change in the images until the fire dies out near the end.
The University of Maryland’s Department of Fire Protection Engineering created this fire whirl using heptane as the fuel in a compartment with four specially-located openings which induced a “whirl” when the exhaust hood was turned on. It was photographed at 300 frames per second. The University’s web site has more information, including a photo of people roasting marshmallows in the flames.
Thanks go out to Daniel