I was looking through some photos taken in March of the prescribed fire along the Fall River in Hot Springs, South Dakota. The flames in this picture got my attention — small chunks of flames continue to exist several feet from the main body of the flames. The photo was taken at a fairly fast shutter speed, 1/500 second.
Click on the photo to see a larger version. I manipulated the colors a bit to make the flames show up more clearly.
Below is a video shot at the project.
More photos of the prescribed fire
Before and after photos of the prescribed fire
Sometimes the camera catches what the eye misses. Nice photos and a reminder about burning flammable vapors.
Doug, I was in a structure fire that flashed over and your description is right on.
Had on full structural PPE and it was all damaged beyond use by the heat.
Whatever is flammable in the gasses coming off that fire will continue to burn until consumed or until the gaseous mixture will no longer support combustion, or until temperature decreases enough to fall beyond the flashpoint of the gasses.
We often see fire whirls well above fuels, and anyone that’s seen a flashover in a structure knows that the atmosphere or gasses around a fire can combust without being near the fuels at all. Flashovers, of course, aren’t generally survivable, but chambers and simulations are designed that allow one inside a room with a flashover, where “snake flames” appear before one eyes as the atmosphere in the room combusts. Neat stuff, for the observer. Otherwise, deadly.
According to the “Luminous Flame” entry at Wikipedia, the visible light of the flame is the glowing incandescence of heated soot particles at the base of the smoke plume. So the transparent areas between the glowing orange portions of the visible flame are merely slightly cooler combustion products that are below the threshold of incandescence. It still looks pretty.