High-speed video of the very rapid deflagration (burning) of a mixture of oxygen and acetylene in a cylindrical mylar bag. Paper describing experiment is: http://chemeducator.org/bibs/0016001/16110279.htm
We filled a 1" diameter bag about 4 ft long up with a near stoichiometric mixture of oxygen and acetylene from a welding torch kit. One end of the bag was ignited with an electric match and we used the high speed video to measure the speed of the flame front as it moved across the frame (distance over time).
It is common for chemistry teachers to demonstrate an oxy-acetylene explosion in their classes or labs by igniting a similar mixture. It makes a loud noise (very loud), but our experiment showed that it is actually a deflagration (burning) rather than a detonation (explosion), the difference being that true detonations produce supersonic reaction speeds. The literature describes methods for creating true detonations, and we've invented methods to simulate both air and underwater blast waves in the lab with oxy-acetylene mixtures.
