A JFSP Fire Science Exchange Network
Bringing People Together & Sharing Knowledge in the Northern Rockies

Watch This Yule Log Burn in the Name of Science

Date: December 20, 2019
Presenter(s): Mark A. Finney, Sara S. McAllister

This Yule Log video—set to a carefully chosen soundtrack—shows various kinds of experiments conducted at the Fire Sciences Laboratory of the U.S. Forest Service’s Rocky Mountain Research Station in Missoula, Montana, just in time for the holiday season. Get cozy and learn more about these intriguing—and oddly satisfying—fire experiments below. At 0:13​, you'll observe the “chimney experiment,” in which the team burns strands of shredded wood under metal tube that is a foot square and about 12 feet tall. This simulates how a tall column of smoke pulls in an influx of fresh air at the bottom, which feeds the fire and blasts straight up. At 3:23​, the second experiment called the “cardboard experiment" begins, which entails placing little, laser-cut cardboard cones at regular intervals and then changing the slope to see how fires spread uphill. The third at 7:03​ is known as the “fire puffing” experiment, which demonstrates how the frequency of “puffing,” or sudden bursts of flame, hot gas, or smoke, is related to the size of the area it burns in. Watch the mesmerizing “fire whirl" at 8:35​. To coax flames to swirl around and around like a vortex, the team sets fire to a bit of alcohol enclosed within a tube with slits in the side.

Topic(s): Fire Behavior, Fuels
Ecosystem(s): None
Type: Video
NRFSN number: 22676
Record updated: Mar 8, 2021