demonstrations:fire_tornado

Fire Tornado

Materials: ★★★ Requires materials not commonly found in school laboratories
Difficulty: ★★☆ Can be done by science teachers
Safety: ★★★ Only to be attempted with adequate safety procedures and trained staff

Categories: Combustion, Global Systems, Weather and Climate, Science Shows

Alternative titles: Spinning Fire Column

Summary

This dramatic demonstration shows how a spinning column of fire can be created using a rotating screen cylinder and a flame source. It models the dangerous fire tornadoes that occur in extreme wildfires when hot air updrafts combine with swirling winds.

Procedure

  1. Roll a metal screen into a cylinder 2.5–3 feet tall, securing it with wire or staples.
  2. Place the cylinder upright on a rotating tray (Lazy Susan), ensuring it is centered.
  3. Set a small glass dish with pieces of sponge in the middle of the tray, ideally on a heat-resistant base.
  4. Soak the sponge pieces thoroughly with lighter fluid.
  5. Put on safety glasses and light the fire. Spin the tray gently without the screen to observe normal flames. Extinguish with a plate.
  6. Relight the fire, place the screen cylinder over it, and spin the tray. The rising hot air will twist into a fire tornado inside the screen.
  7. Remove the screen and extinguish the fire when finished.

Fire Tornado Experiment (Physics) - BeardedScienceGuy:


How to Make a Fire Tornado - Cool Science Demo - TheSpanglerEffect:


📄 Fire Tornado - Steve Spangler: https://stevespangler.com/experiments/fire-tornado/

Variations

  • Experiment with different mesh sizes or thicknesses of screen wire to see how the tornado shape changes.
  • Try using a record player turntable as the rotating platform.

Safety Precautions

  • TEACHERS ONLY – This demonstration should only be performed by trained science demonstrators.
  • Always wear safety glasses when handling fire.
  • Keep a fire extinguisher nearby at all times.
  • Perform in a well-ventilated area away from flammable materials.
  • Never allow students or untrained individuals to handle lighter fluid or the flame.

Questions to Consider

  • Why does the fire not form a tornado without the screen? (The screen transfers angular momentum to the rising air, giving it a spin.)
  • What natural conditions cause fire tornadoes in wildfires? (Strong updrafts of hot air combined with swirling winds through trees and terrain.)
  • Why must the screen cylinder be centered on the tray? (If off-center, the screen wobbles and the tornado effect fails.)
  • How does this model help firefighters understand real fire behavior? (It shows how airflow and heat can combine to create dangerous spinning fire columns.)